add x-gif component
remove unnecessary files
add thumbnail.gif
add setSource listern and src attribute for ceci-definition
add method setSource
Use compiled+minified jquery-ui CSS file.

This saves ~20 HTTP requests.
Merge pull request #2300 from mozilla-appmaker/jquery-ui-css

Use compiled+minified jquery-ui CSS file.
Merge pull request #2283 from marti1125/x-gif

x-gif
trying to make x-gif work
Merge pull request #2301 from Pomax/x-gif

trying to make x-gif work