use gnu make in opium
Merge pull request #1870 from bactrian/sync-prs-1396802363

Sync OCaml compiler PRs
Merge pull request #1869 from Chris00/master

oasis2opam: add constraint oasis < "0.4.2"
Merge pull request #1866 from rgrinberg/master

opium 0.6.2
updated URL and MD5 for v0.0.5
core 111.08.00
Add piqi-0.7.0 and piqilib-0.6.6
Merge pull request #1872 from alavrik/master

Add piqi-0.7.0 and piqilib-0.6.6
Merge pull request #1871 from UnixJunkie/obuild_0.0.5

updated URL and MD5 for v0.0.5
Sync latest compiler pull requests
Merge pull request #1873 from bactrian/sync-prs-1396911601

Sync OCaml compiler PRs
Merge pull request #1852 from janestreet/core-111.08.00

Core 111.08.00
opium 0.6.3
Add gdal 0.1.1
Merge pull request #1874 from rgrinberg/master

opium 0.6.3
Merge pull request #1875 from hcarty/master

Add gdal 0.1.1
Added facebook-sdk version 0.3.1
Sync latest compiler pull requests
opium 0.6.4
Merge pull request #1877 from rgrinberg/master

opium 0.6.4