remove themes engine leftovers

Change-Id: Ia97ef0f221491141947427d6816a195ad704a762
add support for non-OTA builds
Now it's possible to skip OTA package if NO_OTA_BUILD is set to true.
That will allow build of custom (which are un-upgradable) ROM builds.

Change-Id: I7d601586bc6e672faca19f08fdeb28b9cca1c7c4
gestures and additional dictionaries in build-in keyboard
This will return gestures and extended dictionaries that were removed during 4.3 merge.
Very usefule for people wishing to use non-market keybord, for example the one from CM.
Note: CM keyboard is somewhat more advanced since it provides much wider support for secondary
      keys values and languages. CM keyboard can be enabled as part of CM packages pack
      which can be enabled by setting EXTRA_CM_PACKAGES to true.

Change-Id: Ica8b75fb655b86cb4b5063d3641d0ece37a89bee
introduce pa_addons instead of mess with packages, vendor_props and manifests
This introduces pa_addons which combines treatment of vendorprops, packages, manifests and per-device repos.

Effetcs:
* By default everything looks and works the same!
* Add/Remove repos should be more error prone.
* Less code duplication.
* More logical structure.
* CM packages pack aligned with CM10.2 and can be enabled by setting EXTRA_CM_PACKAGES to true.

The new structure is:
* For devices:
    vendor/pa/manifests/DEVICE.{addons,removes} (All vendorprop and per-device repos migrated here)
    vendor/pa/packages/DEVICE.mk
    products/pa_DEVICE.mk (All repos/packages migrated to unified vendor/pa/config/pa_addons.mk

* For packages packs (currently only CM)
    vendor/pa/manifests/PACK.{addons,removes}
    vendor/pa/packages/PACK.mk

* Tools:
    tools/{add,remove}repos.py (replaced tools/{getvendorprops,removeprojects,addprojects}.py)

Change-Id: I9a30032dbe003fc14a0df647045c211075b2f5cc