Update pull-to-refresh

* Add indeterminate progress bar style for pre-Honeycomb
* Fix flickering of ActionBar during syncing on pre-Honeycomb
* Change and extract PullToRefresh texts strings
Simplify and declutter action bars
* Move action bars to the top
* Reorder buttons, show only most important actions, overflow the rest
* Remove help button from Add tasks screen and show it only if there are no projects or contexts to choose from
* Change Add tasks add action button from "save" disk to checkmark
* Don't make Help activity fullscreen, closes #316
* Delete unneeded sync layout and icons
* Delete unneeded icons
* Add icons for menu items (lower than 4.0)
Avoid ArrayIndexOutOfBoundsException on 2.x
https://code.google.com/p/android/issues/detail?id=10238#c6
as per @chuckbjones
Version 1.5-beta2, release 39