pidgin/pidgin

Add a donate link that opens https://imfreedom.org/donate/
release-2.x.y
2021-06-14, Gary Kramlich
13a246aa0656
Add a donate link that opens https://imfreedom.org/donate/

Testing Done:
Ran locally

Reviewed at https://reviews.imfreedom.org/r/749/
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.