PATCH: Note properties that are perl extensions to Unicode in perluniprops.pod

Attached patch changes mktables to add this info.  It should be applied 
after "PATCH:  Change mktables generated documentation to not include 
stuff not going into 5.12".

• PATCH: Note properties that are perl extensions to Unicode in perluniprops.pod by karl williamson
• Re: PATCH: Note properties that are perl extensions to Unicode inperluniprops.pod by karl williamson
• Re: PATCH: Note properties that are perl extensions to Unicode in perluniprops.pod by Rafael Garcia-Suarez