Fixed #775, made sure all the category methods that are public have the sd_ prefix (deprecated the old ones)
-there were a few exceptions where I just renamed the methods since they were added in this method
Added option to use the cached image instead of the placeholder for UIImageView. Replaces #541. Fixes #599
Fixed misspell
Updated README.md with badges
Merge branch 'master' of github.com:rs/SDWebImage