Refs #8632. Fixing system, API and Algorithm doxygen issues.
Refs #8632. Fixing Crystal, DataObjects and Geometry doxygen issues.
Refs #8632. Fixing CurveFitting doxygen errors.
Refs #8632. More doxygen errors.

Fixing DataHandling, Kernel, MDAlgorithms, MDEvents and Nexus.
Refs #8632. Fixing MantidPlot and MantidQt doxygen errors.
Refs #8632. Fixing a missed error.
Revert "Refs #8632. Fixing MantidPlot and MantidQt doxygen errors."

This reverts commit b37ca8023d40d1dea64faf68b6b0bb64fdce564e.
Refs #8632. Fixing some MantidPlot errors.
Merge branch 'master' into feature/8632_doxygen_errors
Refs #8632. Fixing last MantidPlot error.
Refs #8632. Fixing most of the MantidQt errors.
Refs #8632. Fixing some last errors.
Revert "Refs #8632. Fixing some last errors."

Got another conflict that I don't feel like fixing.

This reverts commit 655ba9d6c48090a757adc06f0b3b88b36192651b.
Refs #8632. Fixing some last errors.
Merge remote branch 'origin/feature/8632_doxygen_errors'