Performance improvements and fixes for mail-list
* Use same list style in desktop as mobile
* Bugfix: don't download all body when list not displayed
* Use ng-infinite-scroll to load DOM nodes on demand
* Custom search filter for FTS and reomve angular filters
* Rubber band scrolling on iOS
* Add CSP support in cordova via html meta tag
Merge pull request #93 from whiteout-io/dev/performance

Dev/performance