Merge pull request #713 from sergeyklay/feature-bootstrap-3

Some refinements
New feature: Gleez Upload 1.2.0

New:
 + Added Upload::uploadImage
   Usage:
   // NULL when filed, otherwise file path
   $filepath = Upload::uploadImage($_FILES);

API changes:
 + Renamed Upload::get_max_size to Upload::getUploadMaxFilesize
Updated feature: Added default upload image path, disabled bmp by default