allow underscore and dashes in color aliases
allow underscore and dashes in color aliases

nyimbi/tilemill,nyimbi/tilemill,tizzybec/tilemill,paulovieira/tilemill-clima,MappingKat/tilemill,nyimbi/tilemill,fxtentacle/tilemill,florianf/tileoven,fxtentacle/tilemill,paulovieira/tilemill-clima,mbrukman/tilemill,Teino1978-Corp/Teino1978-Corp-tilemill,mbrukman/tilemill,Zhao-Qi/tilemill,Zhao-Qi/tilemill,MappingKat/tilemill,mbrukman/tilemill,mbrukman/tilemill,paulovieira/tilemill-clima,nyimbi/tilemill,paulovieira/tilemill-clima,Zhao-Qi/tilemill,Zhao-Qi/tilemill,tizzybec/tilemill,isaacs/tilemill,Zhao-Qi/tilemill,MappingKat/tilemill,paulovieira/tilemill-clima,tilemill-project/tilemill,florianf/tileoven,isaacs/tilemill,tilemill-project/tilemill,Teino1978-Corp/Teino1978-Corp-tilemill,Teino1978-Corp/Teino1978-Corp-tilemill,MappingKat/tilemill,tizzybec/tilemill,tilemill-project/tilemill,tizzybec/tilemill,fxtentacle/tilemill,isaacs/tilemill,MappingKat/tilemill,fxtentacle/tilemill,florianf/tileoven,tizzybec/tilemill,Teino1978-Corp/Teino1978-Corp-tilemill,fxtentacle/tilemill,Teino1978-Corp/Teino1978-Corp-tilemill,mbrukman/tilemill,nyimbi/tilemill