Tests: simplify .travis.yml

.travis.yml

@@ -1,16 +1,8 @@
 language: vim
 
-before_script: |
-  hg clone https://vim.googlecode.com/hg vim
-  make -C ./vim
-  git clone https://github.com/junegunn/vader.vim.git
+before_script:
+  - sudo apt-get -qq update
+  - sudo apt-get install -y vim-gtk
 
-script: |
-  VIMRUNTIME=vim/runtime vim/src/vim -XNu <(cat << EOF
-  filetype off
-  set runtimepath+=vader.vim
-  set runtimepath+=.
-  filetype plugin on
-  syntax enable
-  set hidden
-  EOF) -c 'Vader! test/*' >/dev/null
+script:
+    - test/run