Merge pull request #1 from MatthieuStigler/master

use example data
Merge pull request #2 from MatthieuStigler/master

Initial commit of server.R and ui.R for wordcloud
Added color selector dropdown
Applied better reactivity

Fairly thorough re-write of server.R... put all the stuff that used to
be in the reactive function into the renderplot function itself (it's
reactive), Also figured out how to get actionbutton to stop everything.
Few other things, and formatting improvements.
Merge pull request #3 from mexindian/Better-reactivity

Applied better reactivity