Ensure CommonUBForAll cannot be used if there are peaks from only one run present.

Fix TBB Threading issue

Add FullprofPolynomial documentation

Wrap mantiddoc Sphinx logger usage for version 1.2

Replace final header guards with pragma once

Clang-tidy modernize-use-auto Qt

Change behavior of MatrixWorkspace::findY when value=NaN

The sphinx.util.logging framework was not available
in version 1.2 that is currently used by RHEL 7. This wraps
the calls and chooses an appropriate implementation.

Only find OpenGL if it is enabled

Replaces the deprecated scheduler_init with global_control. This should
future proof us, and completely avoids all the threading issues we were
seeing previously.

The TBB_PREVIEW_GLOBAL_CONTROL macro is required until TBB 2019U4, or 11
internally. So for simplicity we will make platforms using an older
version of TBB (RHEL7 and Ubuntu at writing) switch to scheduler init

This commit removes the final header guard that had
been missed by the auto replacer.

re: #28200

Fixes the following assertion thrown by TBB:

	Attempt to terminate non-local scheduler instance

This took a significant amount of time to track down due to a number of
factors. If your looking for a quick fix; set your
tbb::task_scheduler_init to use thread local storage.

This is caused by using Python multi-processing (in our case for the
system tests). The process will spawn correctly (Windows), however
Python will helpfully create seperate thread(s). I assume to observe. In
this case the task_scheduler_init handle would then belong to one of
these threads, as the act of importing our Python module would init the
framework and TBB implicitly.

When the tests run and TBBs scheduling is required it will "sign_on" in
tbb's governor.cpp to handle scheduling. This works because the
scheduler_init handle
is process wide. However internally they then use thread local storage
(TLS) for tracking the scheduler.

As the main process goes to destruct it assumes that we must have
a scheduler instance, since at process level we have done the init.

But we cannot see any schedulers since they belong to a different
thread. We have been getting away with this as the TLS returns NULL
which effectively nops the destruction. But the assert correctly points
out were getting this wrong.

Marking each handle to the scheduler as thread local effectively ties
the destruction of the thread to its init status. For most threads this
effectively means we create a unique_ptr which isn't used. But for our
main threads and weird edge case worker threads it keeps the thread
state consistent.

We've used a unique_ptr since we have an API which allows us to change
the number of threads TBB can spin up. However, anyone else facing this
issue would probably be fine with a thread local object allocated on the
stack.

Remove the dodgy passing of algorithms in *Dialog methods

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

Update logging calls so they work in sphinx v2.3

Add documentation for the thermal neutron back to back functions

Deprecate simpleapi *Dialog functions

Fix TOFTOF reduction script execution

Use cmake generate_mantid_export_header to generate DllConfig.h (Algorithms)

Co-Authored-By: Harrietbrown <49688535+Harrietbrown@users.noreply.github.com>

Replace header guards in tools with pragma once.

They have low to zero usage and at this point are
just a maintenance burden. They do not work in
workbench and are not worth the effort to port.
In the future it would be better to replace input
in workbench with a function that raises a generic
QInputDialog.

Replace header guards in RemoteAlgorithms and RemoteJobManager with pragma once

Replace header guards in TestHelpers and Types with pragma once

Fix Muon and Frequency Domain Analysis GUIs not opening in Plot

updated elemental analysis ref data

Replace header guards in qt/icons and qt/paraview_ext with pragma once

Co-Authored-By: Harrietbrown <49688535+Harrietbrown@users.noreply.github.com>

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

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

Replace header guards in Testing with pragma once.

Replace header guards in MantidPlot with pragma once

Fix Plot Type being in context menu on plot with only one line

Add documentation for UserFunctionMD