add utilities for calculating local and installation theme root dirs
add utilities for calculating local and installation theme root dirs

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