Ticket #3076: fix regression in password recovery when email address given that doesn't match
Ticket #3076: fix regression in password recovery when email address given that doesn't match

Was triggering errors due to use of common_canonical_nickname() on arbitrary input without checking for exceptions about invalid nicknames (which didn't exist long ago in the before time)

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