pidgin/pidgin

Update the documentation for the 2.14.3 release
release-2.x.y
2021-04-08, Gary Kramlich
98f8af044651
Update the documentation for the 2.14.3 release

Testing Done:
Ran `make distcheck` without issue.

Reviewed at https://reviews.imfreedom.org/r/599/
For information on writing a plugin for Purple, Pidgin or Finch, go
http://developer.pidgin.im and click on API. From there, see the
HOWTOs in the "Related Pages" section.
You can also generate this documentation locally by installing
doxygen and graphviz dot, then running "make docs" in the
source tree. The documentation will be in the docs/html directory.