Add analyzers properties.

Add PMD, CheckStyle and FindBugs properties.
Change lint options.
Squashed commit of the following:

commit 84ad83e71276b12c2f86db9b5ae65bba491f59d8
Author: Roman Savin <savin9201@gmail.com>
Date:   Thu Nov 20 14:50:33 2014 +0300

    Fix sample crashes.

    Add AppCompat for both samples applications.
    Add permissions for gcm_migrate_sample.
Fix code analyzers problems.
Refactor adm module.

Use ADMMessageReceiver as parent of ADMReceiver class.
Use ADMMessageHandlerBase as parent of ADMService class.
Rename some class members.
Add some TODOs.
Refactor opfpush module. Add logic with global listener.

Remove MessageListener.
Remove Result class.
Move methods of MessageListener to EventListener.
Add initialization of EventListener one time using Options object.
Fix some checkstyle problems.
Rename ProviderCallback to ReceivedMessageHandler, because this name better describes the purpose of this class.