Modified resolveReferences script.

Modified linkCrossReferences() to permit linking into the
name calculation document (accname-aam.html).  In addition,
modified the name calculation and core mapping documents to use
the script to refer to one another where they formerly used
relative URLs.

Added @id attributes to the individual steps in the "Text
Alternative Computation" section of accname-aam.html to allow
cross referencing of those steps.

Also, removed "Note:" prefix for text styled with class="note".
ACTION-1492/ISSUE-671: Mappings of aria-invalid="<unknown value>"

Fixed mappings where author has provided an unknown value for
@aria-invalid.  In this case, it is mapped to each AAPI's
representation of 'invalid'.

For details, see:
http://lists.w3.org/Archives/Public/public-pfwg/2014Jul/0081.html