Removed AndroidProject super-interface

Deleted AndroidProject super-interface from code. This abstraction
created a common interface for Jawyay Maven android plugin projects
(which we only want to read values from to modify the Eclipse workspace)
and ADT android projects (which we want to read and modify).

These two classes actually unrelated behaviour and a common interface
gives the false impression they can be substituted for each other.

This re-factoring has the benefit of removing several unsupported
operations from classes as well as removing redundant code that is never
called. It also makes the code more type-safe ensuring we can't write
values to the Maven POM.
Fixed test classes being added to bin/classes

Unit test classes are being added to final APK archive because they are
being incorrectly compiled into bin/classes folder. This fixes enhancement

This change only modifies the source output location for compile-scope
source folders (e.g. src/main/java) and leaves others unaltered and
pointing to correct path locations.

Added test unit tests to Android application test project so that we can test
that the src/test/java folder has the correct output folder.

Added integration test to verify the output folder for the
src/test/classes is target/test-classes.

Re-factored common code for finding a classpath entry into a utility method to
avoid repeating code.