pidgin/pidgin

Add support for the author-name-color property to PidginMessage and wire it up in PurpleMessage as well

Testing Done:
Joined a chat and verified names were colored properly as well as in im's.

Reviewed at https://reviews.imfreedom.org/r/744/
subdir('libpurple')
subdir('protocols')
if ENABLE_GTK
subdir('pidgin')
else
pidgin_doc = []
endif
if enable_consoleui
subdir('finch')
else
finch_doc = []
endif
alias_target('doc', libpurple_doc, protocols_doc, pidgin_doc, finch_doc)