This uses the -fix option on clang-tidy to automatically fix all
the unused usings declarations that have crept into Mantid.

re #15289

        712 - AlgorithmsTest_CreateDummyCalFileTest (Failed)
        1181 - MDAlgorithmsTest_LoadMDTest (Timeout)
        1195 - MDAlgorithmsTest_MergeMDFilesTest (Failed)

re #11818

 1. Change the filename reported for nexus files if xml contained within
 1. Stop saving the filename to nexus processed files
 1. removed some unused includes

Still to do:
 1. cache SHA1 checksum if needed
 1. Manually test
 1. update documentation
 1. investigate this error:

ctest -C Debug -J 4 -R LoadEventNexusTest -V

 548: LoadParameterFile-[Error] Bad path syntax: C:\Mantid\Code\Mantid\instrument
\C:\Users\rrc79113\AppData\Roaming\mantidproject\mantid\instrument\HYSPECA_Param
eters.xml. Unable to parse File: in C:/Mantid/Code/Mantid/instrument//C:\Users\r
rc79113\AppData\Roaming\mantidproject\mantid\instrument\HYSPECA_Parameters.xml
548: LoadIDFFromNexus-[Notice] Instrument parameter file: C:\Users\rrc79113\AppD
ata\Roaming\mantidproject\mantid\instrument\HYSPECA_Parameters.xml not found or
un-parsable. Instrument parameter file: C:/Mantid/Code/Mantid/instrument/HYSPECA
_Parameters.xml has been loaded

re #11818

Refs #9926

The converted text is stored in separate .rst files in the docs directory.
Refs #9562

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

re #6485

This reverts commit 0e379fa5.

This reverts commit 2e3e5c70.

This reverts commit 3ab9b121.

Refs #3984 Took the wiki description from every algorithm's wiki page and placed it in a comment in the CPP file (instead of the header file).

Continue obsession with const: ExperimentInfo(MatrixWorkspace)::getInstrument now returns a const instrument. Re #1944.

Eradicate IInstrument. Instrument's the one to talk to now (it was the only descendent class anyway). Re #2041.