Auto merge of #492 - aneeshusa:remove-2016.3-backports, r=larsbergstrom

Remove backported modules now included in our Salt

These modules were backported from Salt 2015.8 or Salt 2016.3, but they
should no longer be necessary now that we are on Salt 2016.3.3.

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.travis.yml

@@ -18,7 +18,7 @@ matrix:
         - SALT_NODE_ID=servo-mac1
         - SALT_FROM_SCRATCH=true
       os: osx
-      osx_image: xcode8
+      osx_image: xcode7.3
     - env:
         - SALT_NODE_ID=servo-linux1
         - SALT_FROM_SCRATCH=true
@@ -44,7 +44,7 @@ matrix:
         - SALT_NODE_ID=servo-mac1
         - SALT_FROM_SCRATCH=false
       os: osx
-      osx_image: xcode8
+      osx_image: xcode7.3
     - env:
         - SALT_NODE_ID=servo-linux1
         - SALT_FROM_SCRATCH=false

.travis/install_salt.sh

@@ -22,12 +22,17 @@ install_salt () {
     elif [[ "${OS_NAME}" == "osx" ]]; then
         printf "$0: installing salt for Mac OS X\n"
         brew update
+        printf "\nhomebrew --version output:\n"
+        brew --version # For debugging
+        printf "\n"
         # Unlink allows switching versions,
         # I wish Homebrew had an atomic operation for pinned upgrades
         if brew list | grep 'saltstack' >/dev/null; then
             brew unlink saltstack
         fi
         brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/9e3a66b6b7ca978bfea86897dcc3391c37f9f0ef/Formula/saltstack.rb
+        # In case we had the same version previously, we need to relink
+        brew link saltstack
     else
         printf >&2 "$0: unknown operating system ${OS_NAME}\n"
         exit 1