Merge pull request #1876 from garborg/metadata-v2

Tag DataArrays v0.2.6
Tag Ipopt v0.1.8
Tag PyCall v0.7.3
Merge pull request #1877 from mlubin/pull-request/859a0a10

Tag Ipopt v0.1.8
Tag Compat v0.2.6
Tag ImageView v0.1.9
Tag Winston v0.11.7
Tag DataArrays v0.2.7