Signed-off-by: Steven Hahn <hahnse@ornl.gov>

Signed-off-by: Steven Hahn <hahnse@ornl.gov>

Also updated class_maker.py

Signed-off-by: Harriet Brown <harriet.brown@stfc.ac.uk>

This commit replaces all header guards in API 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

This avoids having to declare a new interface when a new loader type
is added.

It doesn't generate a symbol for the destructor of the *FileLoader
interfaces unless explicitly defined. All other platforms, including
OS X 10.6, don't show this problem.
Refs #7263

The FileLoaderRegistry can now be asked to search its list of loaders
for the best that matches a given file. It passes along a *Descriptor
object to minimize the number of times the file is opened.

Refs #7263

but users might use it too. Wanted to make a separate ticket for this but trac is down

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.

Refs #3507. Full-move to MVP. Sorry for large checkin, but these things are all dependent and cannot have partially working GUI code.

Refs #3157 Sort our System.h. It was becoming a dumping ground. It should only be touched when absolutely necessary as it affects every file in Mantid. Also combined this with Refs #2345 to sort out DLLExport/DLLImport usage. It's done for Kernel, Geometry and API but stuff in the plugins could do with updating as well.

Do away with MantidPlotReleaseDate.h and have everything in MantidVersion. Turn MantidVersion into a class with static functions so that the part that changes every time can go in a cpp - this means files that include MantidVersion.h (e.g. the enormous ApplicationWindow.cpp) don't get compiled every commit. Re #2722. Also formats date better, which fixes #2246.