Squashes ecgreb:maven branch into a single commit for rebase.

* Updates submodules
* Adds parent and module POMs; adds compiled native dependencies.
* Adds script to install local maven dependencies.
* Removes gradle build config
* Removes submodules
* Remove submodule folders
* Remove dependency installation script
* Moves resources folder to module root.
* Moves AndroidManifest to module root.
* Moves vtm assets into module root.
* Renames vtm native libs.
* Massive pom updates.
* Ignore generated files for apklibs and IntelliJ.
* Fix test error due to execution order.
* Move android-maven-plugin to last stable release
* Collapses project into single maven module (removes parent).
* Moves junit to first in dependency list (above Android SDK).
* Updates Google Play Services to version 15.0.0
* POM cleanup
* Update README.md
Moves TestViewport into new test root.