Extend HTML documentation of base classes for overrides

[prjemian]

HTML documentation pages always reference nicely the base class of each group in a definition file, but it references only the most basic base class! Eg. NXarpes/instrument/source/ references NXsource, but not NXinstrument/NXsource (which may have already extended/overridden NXsource)

[PeterC-DLS]

@prjemian Do you meant reference, eg. NXsource, within the application definition?

[prjemian]

@PeterC-DLS Will this issue be resolved in the next days? Is it necessary to resolve this for release of NXDL now?

[PeterC-DLS]

Not sure if I have time to do this before release, so I'm happy to postpone it.

[prjemian]

@prjemian Do you meant reference, eg. NXsource, within the application definition?

Yes. When an application definition overrides a base class and then, in another part of the application definition, refers to that override, the documentation we build point to the override as it is used.

@sanbrock can provide deeper explanation.

[sanbrock]

A solution to this problem is to add a direct link to the vocabulary item referenced first. E.g.: NXXkappa/ENTRY/definition
definition: (required) NX_CHAR <NXxbase/…/definition>
This is implemented in the PR #1272

[sanbrock]

Similarly, for NXxkappa/entry we should indicate that although its base class type is NXentry, it is actually extending NXxbase/entry, which is already an extended NXentry. We should provide this information by linking the first reference, and not only the very base reference. Hence, it should look like:
entry: (required) NXentry <NXxbase/entry>