Register PropertyGraph
Merge branch 'metadata-v2' of git://github.com/JuliaLang/METADATA.jl into metadata-v2
Tag PropertyGraph v0.0.1
Merge pull request #1 from PhillP/pull-request/74bd2ffb

Tag PropertyGraph v0.0.1
Merge pull request #1704 from PhillP/pull-request/9d39de97

Register PropertyGraph.jl