Fixes search weirdness (take 2).

* Updates search results when performing a second search while first is still showing on the screen.
* Uses .replace() to ensure new results fragment is shown each time and does not add transaction to back stack.
* Explicitly removes pager results fragment when search is collapsed rather than relying onBackPressed().
Fixes test errors resulting from vtm-android update.

* Renames ItemizedIconLayer -> ItemizedLayer in MapFragmentTest.
* Returns a new TestMap via getMap() in ShadowMapView.
* Registers TestMap via MapView in TestHelper.initBaseActivity().
* Renames getViewport() -> viewport() in TestMap.
* Adds @Config(emulateSdk = 18) to all test classes (Robolectric does not yet support API 19).
* Fixes checkstyle errors in Feature and MapFragment.
Merge pull request #32 from hjanetzek/master

vtm got gradle
Merge pull request #31 from mapzen/fix-search-weirdness-take-2

Fixes search weirdness (take 2).
Merge pull request #33 from mapzen/vtm-android-gradle-update

Fixes test errors resulting from vtm-android update.
adds path to ndk in library
adds notes about code contributions
adds ndk compile so it will run cleanly in default task
noting that gradle needs a inital run to succeed
Merge pull request #34 from mapzen/baldur/quick_update_to_build_and_readme

Baldur/quick update to build and readme
this step is infact not needed
Merge pull request #35 from mapzen/baldur/quick_update_to_build_and_readme

this step is infact not needed
updating build tool version
updates volley build file
correcting submodule