1.Add Maven support.
2.Workaround to prevent weird test fail of CustomHighRepJobPolicy class in AppEngineUsersConnectionRepositoryTest.java.
1.Bump version to 1.1.0.BUILD-SNAPSHOT(same as Spring Social).
2.Bump Spring version to 4.0.2.RELEASE.
3.Bump Spring Security version to 3.2.0.RELEASE.
4.Bump Spring Social version to 1.1.0.BUILD-SNAPSHOT.(Added temporary workaround for SOCIAL-355: Persistent session managment - NotSerializableException for OAuth2Connection and OAuth1Connection)
5.Workaround in SocialAuthenticationToken class for SOCIAL-355: Persistent session managment - NotSerializableException for OAuth2Connection and OAuth1Connection). (Double fix #4 since it's temporary workaround.)
6.Workaround in ProviderSignInAttempt class for SOCIAL-203: ProviderSignInAttempt - NotSerializableException: ConnectionFactoryRegistry.
Workaround in SocialAuthenticationProvider class for SOCIAL-402: SocialAuthenticationProvider should support multiple connections.
Add app engine datastore namespace support.
Update README.md.
Remove unnecessary elements in pom.xml.
Merge branch 'feature/bumping-dependent-version' into develop
Merge branch 'develop'