When expanding lib_dirs, don't crash with 'volumerelative' paths
When expanding lib_dirs, don't crash with 'volumerelative' paths

choptastic/rebar,shkumagai/rebar,kellymclaughlin/rebar3,platinumthinker/rebar,csyangchen/rebar,SiDen/rebar,norton/rebar,syl20bnr/rebar,rebar/rebar,platinumthinker/rebar,apache/couchdb-rebar,djnym/rebar3,jacktang/rebar,matwey/rebar,tsloughter/rebar3,sile/rebar3,zugolosian/rebar3,project-fifo/rebar3,heroku/rebar,heroku/rebar,jbalint/rebar3,erlang/rebar3,dcarastan/rebar,scatterbrain/rebar,rebar/rebar3,zugolosian/rebar3,lrascao/rebar,CMoH/rebar,fauxsoup/rebar3,paulo-ferraz-oliveira/rebar,jacktang/rebar,basho/rebar,bsmr-erlang/rebar,oubiwann/rebar,cloudant/couchdb-rebar,beni55/rebar,blt/rebar3,evnix/rebar,GabrielNicolasAvellaneda/rebar,evnix/rebar,CMoH/rebar,shkumagai/rebar,matwey/rebar,fishcakez/rebar3,matwey/rebar,RubberCthulhu/rebar,fabiankrol/rebar3,surik/rebar3,shkumagai/rebar,paulo-ferraz-oliveira/rebar,dcarastan/rebar,matwey/rebar,fauxsoup/rebar3,K2InformaticsGmbH/rebar,saleyn/rebar3,evnix/rebar,wcy123/rebar,rebar/rebar,lrascao/rebar,cloudant/couchdb-rebar,matwey/rebar,benoitc/rebar3,project-fifo/rebar3,ferd/rebar3,syl20bnr/rebar,cloudant/couchdb-rebar,walrusVision/rebar3,macintux/rebar,K2InformaticsGmbH/rebar,macintux/rebar,oubiwann/rebar,beni55/rebar-1,bsmr-erlang/rebar,csyangchen/rebar,scatterbrain/rebar,paulo-ferraz-oliveira/rebar,lrascao/rebar,bsmr-erlang/rebar,K2InformaticsGmbH/rebar,processone/rebar3,vladdu/rebar3,deadok22/rebar,norton/rebar,jbalint/rebar3,beni55/rebar,rebar/rebar3,platinumthinker/rebar,sile/rebar3,CMoH/rebar,oubiwann/rebar,benoitc/rebar3,apache/couchdb-rebar,syl20bnr/rebar,GabrielNicolasAvellaneda/rebar,jacktang/rebar,processone/rebar3,bsmr-erlang/rebar,rebar/rebar,scatterbrain/rebar,fabiankrol/rebar3,surik/rebar3,K2InformaticsGmbH/rebar,walrusVision/rebar3,macintux/rebar,norton/rebar,lrascao/rebar3,SiDen/rebar,choptastic/rebar,lpgauth/rebar,csyangchen/rebar,lpgauth/rebar,SiDen/rebar,deadok22/rebar,blt/rebar3,choptastic/rebar,beni55/rebar,lrascao/rebar,K2InformaticsGmbH/rebar,apache/couchdb-rebar,norton/rebar3,norton/rebar,linearregression/rebar3,wcy123/rebar,GabrielNicolasAvellaneda/rebar,RubberCthulhu/rebar,basho/rebar,beni55/rebar-1,lpgauth/rebar,linearregression/rebar3,lrascao/rebar,dcarastan/rebar