pidgin/pidgin

A bunch of random libpurple documentation fixes

2021-08-04, Gary Kramlich
d0abbb616bea
A bunch of random libpurple documentation fixes

Testing Done:
Build the docs and verified the fixes in `build/doc/reference/libpurple/libpurple-undocumented.txt`

Reviewed at https://reviews.imfreedom.org/r/872/
libpurple/data/purple-url-handler.desktop.in
libpurple/protocols/null/nullprpl.c
pidgin/data/im.pidgin.Pidgin.desktop.in
sub/libpurple/data/purple-url-handler.desktop.in
sub/libpurple/protocols/null/nullprpl.c
sub/pidgin/data/im.pidgin.Pidgin.desktop.in