travis: bump vala version for travis builds

.travis.yml

@@ -5,11 +5,11 @@ language: c
 compiler:
   - gcc
 env:
-  - VALAC=valac-0.30
+  - VALAC=valac-0.32
 before_install:
   - sudo add-apt-repository -y ppa:vala-team/ppa
   - sudo apt-get update -qq
-  - sudo apt-get install -qq ${VALAC}
+  - sudo apt-get install -qq ${VALAC} valac
   - sudo apt-get install -qq libgirepository1.0-dev
   - sudo apt-get install -qq gir1.2-gee-0.8 libgee-0.8-dev
   - sudo apt-get install -qq gir1.2-json-1.0 libjson-glib-dev