Use $_REQUEST instead of $_GET for the file name param getters.

Thanks @vvinhas for the comment:
https://github.com/blueimp/jQuery-File-Upload/commit/f44f773c9c3e400b420
c8a5de7760bf3b4d652ce#commitcomment-6606586
Don't throw an error if flushing the output buffer fails. Closes #3201
Updated version number for last commit.