Try some optimization to speed up start up time. Clean up.

Mentionned in PR #169, this is an attempt to limit the space search for RoboGuice when injecting stuff. It will discard a few classes that can't receive injections. 

The main Idea is expressed by the javadoc of the new GuiceInjectionMonitor's javadoc : 

    /*
     * Monitors the state of type hierarchy when injecting a given type via Guice.
     * This class allows to prune the type hierarchy when looking for injection points.
     * It is based on the following observations : 
     * <pre> <i>
     * If a class A extends B and B extends C,
     * then if B is inside android package, then B can't 
     * contains injections points.
     *
     * If B is inside RoboGuice package, or "subpackages", then it may
     * receive injections. A is probably a custom app class or a roboguice test
     * and it may contain injections as well. But if C doesn't belong to roboguice,
     * then we went too high inside the type hierarchy and it's not worth having a look
     * at class C and ascendants.
     * </i></pre>
     * @author SNI
     */

I am afraid of the impact on obfuscation, and would love to hear from any given measure of the optimization, apart from rationale and experience.

I this track is valid, there might be even harder optimizations to find like only making Views or Activities or Fragment aware of view injections, stuff like that.

BTW, I would be at ease to add testing if the PR is accepted.