scons: make sure to still link to libagg even if internal lib is not used - need because before r1196 we were not filtering out libs
scons: make sure to still link to libagg even if internal lib is not used - need because before r1196 we were not filtering out libs

yohanboniface/python-mapnik,mbrukman/mapnik,naturalatlas/mapnik,jwomeara/mapnik,yiqingj/work,rouault/mapnik,rouault/mapnik,naturalatlas/mapnik,garnertb/python-mapnik,jwomeara/mapnik,davenquinn/python-mapnik,mbrukman/mapnik,Uli1/mapnik,strk/mapnik,mapnik/mapnik,yohanboniface/python-mapnik,pnorman/mapnik,mapnik/python-mapnik,CartoDB/mapnik,strk/mapnik,kapouer/mapnik,tomhughes/python-mapnik,zerebubuth/mapnik,Mappy/mapnik,qianwenming/mapnik,manz/python-mapnik,davenquinn/python-mapnik,yiqingj/work,whuaegeanse/mapnik,pnorman/mapnik,mapnik/mapnik,garnertb/python-mapnik,zerebubuth/mapnik,mbrukman/mapnik,Airphrame/mapnik,yiqingj/work,mbrukman/mapnik,pnorman/mapnik,kapouer/mapnik,stefanklug/mapnik,tomhughes/python-mapnik,CartoDB/mapnik,pramsey/mapnik,sebastic/python-mapnik,mapycz/python-mapnik,cjmayo/mapnik,lightmare/mapnik,Airphrame/mapnik,zerebubuth/mapnik,mapnik/mapnik,Airphrame/mapnik,mapycz/python-mapnik,strk/mapnik,Mappy/mapnik,whuaegeanse/mapnik,tomhughes/mapnik,manz/python-mapnik,sebastic/python-mapnik,davenquinn/python-mapnik,Uli1/mapnik,pramsey/mapnik,rouault/mapnik,qianwenming/mapnik,sebastic/python-mapnik,cjmayo/mapnik,naturalatlas/mapnik,tomhughes/mapnik,Mappy/mapnik,cjmayo/mapnik,mapycz/mapnik,tomhughes/python-mapnik,yohanboniface/python-mapnik,Uli1/mapnik,qianwenming/mapnik,strk/mapnik,jwomeara/mapnik,mapycz/mapnik,stefanklug/mapnik,manz/python-mapnik,lightmare/mapnik,qianwenming/mapnik,mapnik/python-mapnik,kapouer/mapnik,pramsey/mapnik,Uli1/mapnik,pnorman/mapnik,tomhughes/mapnik,pramsey/mapnik,tomhughes/mapnik,garnertb/python-mapnik,lightmare/mapnik,jwomeara/mapnik,cjmayo/mapnik,Airphrame/mapnik,mapycz/mapnik,naturalatlas/mapnik,lightmare/mapnik,kapouer/mapnik,mapnik/python-mapnik,stefanklug/mapnik,whuaegeanse/mapnik,yiqingj/work,Mappy/mapnik,CartoDB/mapnik,whuaegeanse/mapnik,stefanklug/mapnik,rouault/mapnik,mapnik/mapnik,qianwenming/mapnik