v0.7.4b: restructured initialization logic into new android module

A lot of cleanup is needed for this, but everything works

android/proguard-rules.pro

@@ -0,0 +1,28 @@
+# retain these to support class references for the bundling and translation systems
+-keepnames class com.shatteredpixel.** { *; }
+-keepnames class com.watabou.** { *; }
+
+# retained to support meaningful stack traces
+# note that the mapping file must be referenced in order to make sense of line numbers
+# mapping file can be found in core/build/outputs/mapping after running a release build
+-keepattributes SourceFile,LineNumberTable
+
+-dontwarn android.support.**
+-dontwarn com.badlogic.gdx.backends.android.AndroidFragmentApplication
+-dontwarn com.badlogic.gdx.utils.GdxBuild
+-dontwarn com.badlogic.gdx.physics.box2d.utils.Box2DBuild
+-dontwarn com.badlogic.gdx.jnigen.BuildTarget*
+
+-keepclassmembers class com.badlogic.gdx.backends.android.AndroidInput* {
+   <init>(com.badlogic.gdx.Application, android.content.Context, java.lang.Object, com.badlogic.gdx.backends.android.AndroidApplicationConfiguration);
+}
+
+-keepclassmembers class com.badlogic.gdx.physics.box2d.World {
+   boolean contactFilter(long, long);
+   void    beginContact(long);
+   void    endContact(long);
+   void    preSolve(long, long);
+   void    postSolve(long, long);
+   boolean reportFixture(long);
+   float   reportRayFixture(long, float, float, float, float, float);
+}