Pin blosc to 1.14.3 for travis-27 build
This reverts commit 52e186af3e0fed9415a2db9e0c8d7d75d1267a54.

xref https://github.com/pandas-dev/pandas/issues/22427 and https://github.com/pandas-dev/pandas/pull/22424
Travis has passed. Merging this since the environment change only affects travis, and the code changes are currently broken on master.