Add simple tests to make sure themes don't contain language errors.

Update readme with travis status.

.travis.yml

@@ -0,0 +1,27 @@
+language: vim
+
+cache:
+  directories:
+    - $HOME/.vvm
+
+before_install:
+  - curl https://raw.githubusercontent.com/kana/vim-version-manager/master/bin/vvm | python - setup; true
+  - source ~/.vvm/etc/login
+  - vvm update_itself
+  - vvm use vimorg--v8.1.1280 --install --with-features=huge
+
+before_script: |
+  git clone https://github.com/junegunn/vader.vim.git
+  git clone https://github.com/vim-airline/vim-airline
+  find $PWD/autoload/airline/themes -name "*.vim" > themes.txt
+
+script: |
+  vim -Nu <(cat << VIMRC
+  filetype off
+  set rtp+=vader.vim
+  set rtp+=vim-airline
+  set rtp+=.
+  set rtp+=after
+  filetype plugin indent on
+  syntax enable
+  VIMRC) -c 'Vader! test/*' > /dev/null

README.md

@@ -1,4 +1,4 @@
-# vim-airline-themes
+# vim-airline-themes [![Build Status](https://travis-ci.org/paroxayte/vim-airline-themes.svg?branch=tests)](https://travis-ci.org/paroxayte/vim-airline-themes)
 
 This is the official theme repository for [vim-airline][11]
 

test/airline-themes.vader

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+# Make sure that theme and 5 basic modes don't throw an error
+# Get list of all included themes
+Execute (validate themes):
+  let themes = readfile('themes.txt')
+  call sort(themes)
+
+  let err_proc = v:false
+  try
+
+    for themePath in themes
+
+      " Check all the basic modes and their modified counterparts
+      " This test only fails on exceptional cases
+      let theme = fnamemodify(themePath, ':t:r')
+      Log theme
+      execute('AirlineTheme ' . theme)
+      execute('source ' . themePath)
+      normal i
+      normal :
+      normal R
+      normal v
+      setlocal mod
+      normal i
+      normal :
+      normal R
+      normal v
+      setlocal nomod
+
+    endfor
+
+  catch
+    let err_proc = v:true
+    Log "Failed validation testing with exception:"
+    Log string(v:exception)
+  endtry
+  AirlineRefresh
+
+  Assert !err_proc