make User_group use caching staticGet()
make User_group use caching staticGet()

charlycoste/StatusNet,furtherfield/gnu-social,charnimda/lgbtpzn-social,sikevux/bsk-social,faulteh/gnu-social,studio666/gnu-social,bankonme/gnu-social,charlycoste/StatusNet,eXcomm/gnu-social,minmb/statusnet,sikevux/bsk-social,Piratas/tortuga,xebia/statusnet-oauth2,gnusocial/mainline,minmb/statusnet,bankonme/gnu-social,csarven/statusnet,foocorp/gnu-social,sikevux/bsk-social,minmb/statusnet,UngPirat/freesocial,bankonme/gnu-social,UngPirat/freesocial,sikevux/bsk-social,studio666/gnu-social,d3vgru/StatusNet,bankonme/gnu-social,xebia/statusnet-oauth2,foocorp/gnu-social,csarven/statusnet,xebia/statusnet-oauth2,zcopley/StatusNet,furtherfield/gnu-social,faulteh/gnu-social,charnimda/lgbtpzn-social,furtherfield/gnu-social,eXcomm/gnu-social,gnusocial/mainline,zcopley/StatusNet,UngPirat/freesocial,faulteh/gnu-social,furtherfield/gnu-social,eXcomm/gnu-social,csarven/statusnet,gnusocial/mainline,studio666/gnu-social,studio666/gnu-social,zcopley/StatusNet,gnusocial/mainline,chimo/social,charlycoste/StatusNet,d3vgru/StatusNet,charnimda/lgbtpzn-social,d3vgru/StatusNet,Piratas/tortuga,foocorp/gnu-social,Piratas/tortuga,chimo/social,eXcomm/gnu-social,chimo/social,faulteh/gnu-social,Piratas/tortuga,csarven/statusnet