Updating licensing links
Info on how to set max imagine size

Adds info to readme on how to setup a maximum width of images uploaded.
Merge pull request #119 from MikeRogers0/maximum_image_size

Info on how to set max imagine size
Merge pull request #117 from MikeRogers0/master

Updating licensing links
Merge branch 'master' of github.com:SammyLin/redactor-rails
FileType for presentation added