Adding configuration for ack plugin
Squashed 'bundle/ack/' content from commit 303bcef

git-subtree-dir: bundle/ack
git-subtree-split: 303bceff1c8ab1145d114083582b1aeac9de7a85
Merge commit '7d1b881e7f1701fa4d2b4ed8941418fd9914059f' as 'bundle/ack'
Help tags for L9/autocomplpop/spacejam/vim-textobj-user plugins
Disable autocompletion of keywords in buffer