Add @anchor for FAQ @nodes, use it for xrefs. Avoids `.' in xrefs
What
Add @anchor for FAQ @nodes, use it for xrefs. Avoids `.' in xrefs. Idea from Aidan Kehoe. Thanks for investigating and the suggested solution.
Why
Periods in node names in xrefs gives warnings like this: @xref node name should not contain `.'. This is avoided in the MR by letting the xref refer to an anchor with the periods replaced with underscores and letting the xref display value be the node name with the period.
Note
The resulting info files produced by makeinfo 7.1 works fine in GNU Emacs. Both display of references and links work fine. It does however not work with current info.el in XEmacs. The info file is displayed with multiple problems. The MR, if otherwise reviewed to be good, should probably not be merged until info.el is fixed.