Update README.rdoc
Update Gemfile

CMS sometimes introduces breaking changes with 'minor' updates that may require migrations and stuff (upcoming 1.12.0). Patch updates are always save though.
Merge pull request #4 from GBH/patch-1

Fixing CMS version dependency
updated bundler
remove ruby version files
Version bump to 1.1.3
generate gemspec
merge new master updates
added image attach function
fixed file images urls