Fix for earlier version of docutils.

The code role was introduced in 0.9 but a lot of places still use 0.8
Refs #9749
Fix a few more docs errors.

Refs #9749
Fix more docs sphinx errors.

Refs #9749
Merge branch 'bugfix/9749_fix_remaining_sphinx_errors' into develop

Conflicts:
	Code/Mantid/docs/source/algorithms/RadiusSum-v1.rst