specify MB_ML_VER in .travis.yml

Author: jswhit

.travis.yml

@@ -1,12 +1,14 @@
 env:
     global:
         - REPO_DIR=netcdf4-python
-        - BUILD_COMMIT=v1.5.5rel2
+        - BUILD_COMMIT=v1.5.5.1rel
         - PLAT=x86_64
         - UNICODE_WIDTH=32
         - NP_BUILD_DEP=1.17.3
         - NP_TEST_DEP=1.17.3
         - WHEELHOUSE_UPLOADER_USERNAME=travis-worker
+        # manylinux version to build (1, 2010 or 2014)
+        - MB_ML_VER=2014
         # Following generated with
         # travis encrypt -r MacPython/netcdf4-python-wheels WHEELHOUSE_UPLOADER_SECRET=<the api key>
         - secure:

config.sh

@@ -7,7 +7,6 @@ export NO_NET=1
 export MACOSX_DEPLOYMENT_TARGET="10.9"
 export NETCDF_VERSION="4.7.4"
 export HDF5_VERSION="1.12.0"
-export MB_ML_VER=2014
 
 source h5py-wheels/config.sh