added Foursquare and XING Providers
added Foursquare and XING Providers

mslinn/securesocial,bgarrels/securesocial,normenmueller/securesocial,mchu4545/securesocial,jaliss/securesocial,jaliss/securesocial,didmar/securesocial,k4200/securesocial,matthewchartier/securesocial,matthewchartier/securesocial,jaliss/securesocial,jaliss/securesocial,matthewchartier/securesocial,mchu4545/securesocial,didmar/securesocial,normenmueller/securesocial,mslinn/securesocial,k4200/securesocial,k4200/securesocial,bgarrels/securesocial,didmar/securesocial,didmar/securesocial,sejkorat/securesocial,sejkorat/securesocial,sejkorat/securesocial,bgarrels/securesocial,mslinn/securesocial,mchu4545/securesocial,normenmueller/securesocial,jaliss/securesocial,mslinn/securesocial,matthewchartier/securesocial,normenmueller/securesocial,k4200/securesocial,mchu4545/securesocial,sejkorat/securesocial,bgarrels/securesocial,sejkorat/securesocial