Update compiler version

Author: garyb

.travis.yml

@@ -3,7 +3,7 @@ dist: trusty
 sudo: required
 node_js: stable
 before_script:
-  - TAG=v0.12.0
+  - TAG=v0.12.3
   - wget -O $HOME/purescript.tar.gz https://github.com/purescript/purescript/releases/download/$TAG/linux64.tar.gz
   - tar -xvf $HOME/purescript.tar.gz -C $HOME/
   - chmod a+x $HOME/purescript