[AndyB] Upload manager 1.0

Converts uploaded PNG images to JPG images.

PNG images are very wasteful as they are 10 times the size of a JPG image of same size. This add-on will convert PNG imaage to JPG images in the following areas which use the editor: thread posts, conversation messages, resource manager and media manager.

Questions and answers:
Q: Will it work if I paste an image into the editor?
A: Yes.
Q: I'm using an Apple retina display, will images pasted from the clipboard be correctly resized with this add-on?
A: Yes.