change PunditAdapter to work with method_missing
remove js window.AA
simplify AA::Devise.config

Devise has `sign_out_via` since v1.2.0 (ab7f3bc1757104c053d3e3c9bf6db2de03dee830), and we have a min (soft) dependency to v3.2.x https://github.com/activeadmin/activeadmin/blob/master/lib/active_admin/dependency.rb#L3
Fix linter errors

* Removed duplicated newlines
* Replaces ASCII Chars
Replaces datepicker images with css, uses bourbon for gradient, and set colors from variables file
Merge pull request #3641 from philipgiuliani/patch-1

Fix linter errors
Merge pull request #3644 from cohart/3565-style-date-picker-via-css

Replaces datepicker images with css, uses bourbon for gradient, and set ...
Merge pull request #3606 from activeadmin/remove_js_aa

remove js window.AA
Merge pull request #3607 from activeadmin/simplify_devise_config

simplify AA::Devise.config
Merge pull request #3593 from activeadmin/3406_pundit_method_missing

change PunditAdapter to work with method_missing
fix devise/passwords/edit markup

closes #3651
use `devise_error_messages!` in the same view like deivse does
use 1.9 hash syntax in erb all files
remove travis_cache
setup appraisal
change travis setup
strip off detect_rails_version
Try out the new beta build environment

- removed the time tags (this is built into Travis)
- use the new LXC build env on EC2
- use built in caching
don't bundle install the dev group

and make sure we bundle update