Merge pull request #1039 from thiagocatarse/bootstrap

Bootstrap
fixed project submit button in the bottom of start page
just check is mixpanel is available (may cause problems in development but I'm trying to solve a tracking problem in production mode)
adding ref bck to home banner link
enabled fog in carrierwave for development environment when we have the AWS key in settings
fixing JS for development env
updating pagarme gem to fix problem with payment slip
fixing duplicated contributions in project page
adding dependent destroy to improve error handling in users bank account
add dashboard user about tab
change travis ruby version
Merge pull request #1041 from adrianob/dashboard_user

add dashboard user about tab
move online validators to custom validator class
include more state validations
fixes project scope spec that should use match_array
add project preview tab
use url helper
Fixes mixpanel in beta
updated gem browser
refactor project state machine specs