Force use of the 24.3 emacs

Author: ardumont

.travis.yml

@@ -27,7 +27,7 @@ before_install:
   - make deps
   - cask --version
     # install the matrix's emacs version (except for 24.3 which is already installed)
-  - evm install $EVM_EMACS --use --force || echo "Already installed - Skip."
+  - evm install $EVM_EMACS --use --force
   - emacs --version
   - env | grep -i emacs