Merge pull request #1 from mposolda/GTNPORTAL-2918

Refactoring according to latest GateIn changes in oauth branch
GTNPORTAL-2918 - refactoring fo css/xml
GTNPORTAL-2918 - more refactoring
Adding OAuthPortletFilter and save accessToken to portletSession, so it's available in all phases of portlet lifecycle
Added FacebookRequest and using it in FacebookUserInfoPortlet