OpenSnap 0.2

Server
 * Use Spring Framework 4.0.3.RELEASE (no more forked Spring needed)
 * Spring Security based security
 * Java 8 based
 * The application can now be ran as a WAR or executable JAR
 * Improved Gradle configuration, include symlink for Dart client files
 * Snap asynchronous notification
   (still need some work for clusters support)

Client
 * Improved event management
 * Snap notifications
 * Fix UI bugs
 * AngularDart 0.9.8 -> 0.9.10
 * All lib dart files are part of opensnap library
 * Http based authentication in order to work with
   Spring Security