How to deal with/disable attributes raising issues with SWIG, compiler warnings, doxygen,...?

[jim-bcom]

PROBLEM
These custom attributes sometimes trigger issues in certain contexts and we would like to ignore them.

• In PR Remove as much warnings as possible #63, these attributes are disabled via XPCF macros in order to remove compiler warnings.
• in this comment, it's doxygen that is supposed to have trouble with them.

ACTIONS

• first we want to check the status with doxygen concerning this comment. Is the guard well placed, or is it also required for the other attributes? Are we using DOXYGEN_SHOULD_SKIP_THIS properly?...
• find a solution for doxygen, check if the one used in the PR aimed at removing warnings can work instead of using DOXYGEN_SHOULD_SKIP_THIS.