Update plugins that moved off Bitbucket.
Shorten GitHub raw links for plugin logos.
Fix plugin links to anchors.
Use https links where available.
Update some redirecting links.
Testing Done:
Viewed the result, and logos didn't seem to break. Some were even fixed now due to Bitbucket repo deletion.
Reviewed at https://reviews.imfreedom.org/r/72/
These files were generated at http://faviconit.com/