Implement PNG format for screenshot
Screenshot are now only available in TGA or JPG format. Add PNG as a better (default) screenshot format.
Also, reduce the screenshot command to one (so it’s less annoying in console, especially in dev mode) and see if TGA code can be removed entirely.
/screenshot is now using JPEG format. Making a screenshot using TGA format isn’t possible anymore, but the underlying code is still there. It could be accessed again with a new r_screenshotType(?) when PNG is also added.
implement PNG rendering(done) add a r_screenshotType cvar to define format(done, using r_screenshotFormat) rework cl_avidemoType (0 and 2 are now JPEG, TGA is not an option anymore)(ok, use above mentioned cvar) adjust UI for new r_ cvar(done in system options) move screenshot code in rendercommon (guess it could be shared across all renderers)(too messy to get it right, so that’s for another time if ever)