Runs clang-tidy pass by ref across the codebase to fix-up various
warnings we are seeing in cppcheck

Also updated class_maker.py

This commit replaces all header guards in DataHandling with #pragma once

Update copyright headers in all files

Squashed commit of the following:

* First version of a script to manage copyright statements

re #23468

* Neatened up script, added comments

re #23488

* move script to tools directory

re #23488

* small script changes and a couple of manual file changes

re #23488

* Minor chnage to whitespace detection in regex

re #23488

* Add an excluded directory

re #23488

* remove a repeasted copyright statement in a file

re #23488

* Don't comsume the comment end if it is on the same line

re #23488

* fix error in new copright parsing

re #23488

* remove double copyrifght entry

re #23488

* Improve handling of old copyrights at the start of comments

re #23488

* remove empty comments re #23488

* exclude gsoapgenerated directories

re #23488

* Sort out greedy line matching re #23488

* improve empty comment removal

re #23488

* improve false positives

re #23488

* impressive speedup by limiting regex matching length

re #23488

* remove evil invisible non ascii character

Also upadte the copyright at the same time

re #23488

* resolve multiple copyrights in a single file

re #23488

* resolve an issue with new statement detection

re #23488

* another unprintable unicode character

re #23488

* pep updates and cmake the new copyright fit clang format

re #23488

* update already done new format headers

re #23488

* wrong type of bracket

re #23488

* Update class_maker and friends

re #23488

* Update all copyright statements

re #23488

* clang format re #23488

* flake8 warnings re #23488

* Flake8 warnings re #23488

* Exclude .cmake.in and rb.in files

re #23488

* replace missing line re #23488

* exclude .py.in files as they are flasely recognized as C++

re #23488

* another setp.py.in re #23488

* another .py.in correction re #23488

* Hopefully the last of the .py.in files re #23488

* resolve utf-8 encoding of python files and changed ABINS checksum

re #23488

* updates to unit tests that reference line numbers

re #23488

* remaining unit test files and other fixes

re #23488

# Please enter a commit message to explain why this merge is necessary,
# especially if it merges an updated upstream into a topic branch.
#
# Lines starting with '#' will be ignored, and an empty message aborts
# the commit.

Merge done to enable documentation be be fixed, because of removal of
alias directive and addition of related algorithms directive.

Signed-off-by: Karl Palmen <karl.palmen@stfc.ac.uk>

re #22143

This reverts the changes to Load from commits
  - 67348e40
  - cf334a95

We need a better way for a specific loader to request that it will handle
all files that Load has found.
Refs #10061

In the case of LoadEventPreNexus is is "EventFilename". It seems that for
everything else is is "Filename" because the variable that holds this is
empty by the time the algorithm comes to run (though the loader is
selected correctly).
I've factored out the method that sets the variable and called it again
from within a method that exec() calls.

Avoids loading everything then summing in separate loop, instead loads then sums in same
loop

This reverts commit 4fe9cd9d, and fixes
tests.

This reverts commit a9c8a59a.

Allow filenames specified with the format <<short><operator>>...<short>
where:

<short> = <dir><inst><underscore><runs><ext>
<operator> = "+" or ","
<runs> = lists and/or ranges of (possibly added) runs e.g. "12,13+14,15:20".

See header file of MultipleFileProperty for more info on syntax.

This enables workspaces loaded through the algorithm to have a history that
can be used to reproduce the workspace properly.

MWRunFiles widget of LoadDialog now remembers the exact text a user typed -
in this way any user who types "INST0-50", clicks "Run" and reopens the
dialog is not met by a huge string containing a list of all 51 fully
resolved files, but rather their original input.

Changed the vector<vector<string>> templated versions of the toString and
toValue functions to accept customised delimiters.  This enables us to add
an option for the user to turn off multifile parsing if they are crazy
enough to want to load files with a plus or a comma in their path.

Changed the inner workings of Load for multi files.  No longer calling sub
algorithms with setChild or alwaysStoreInADS.  All workspaces are
essentially created outside the ADS and managed by the algorithm, right up
until the OutputWorkspaces are set.

Tests added where appropriate, but the majority of parsing cases are already
covered by MultiFileNameParser.

MultiFileProperty changed to store a vector of vectors of file names. File
names that share a vector are to be added. Old functionality can be produced
by calling "flattenFileNames".  See source code for more info.

MultiFileProperty was used in one place previously (MDMergeFiles), this has
been modified to relect these changes.

Load now implemented in terms of MultiFileProperty, though its interface is
unchanged.  "Filename" input is now parsed as a multi file, and if that
fails old functionality is attempted.  Error reports will output the result
of both attempts.

Some additional template specialisations / "toString" overloads
surrounding the Property class heirachy were necessary to properly support
std::vector<std::vector<std::string> >.

Refs #3724: Pulled wiki description text from the wiki site and added in algorithms' header file with special tags. The auto_wiki.py script can retrieve the text to generate the wiki page fully.

1) I don't think anything should be done here as fast algorithms may not be possible to cancel anyway.
2) Made Algorithm::cancel() method virtual and overridden it in Load to call cancel() on the concrete loader. A test file can be sans2d00005512.nxs.
3) MantidPlot makes sure that the AlgorithmDockWidget is visible when an algorithm is running. fixes #1733

Fixes #2839. Make the error message from the Load algorithm much clearer if it can't find an appropriate loader.