Fixes #15 - adds tab-completion for app() function
Improves directory searching for app() function

Now searches:

$(dirname $dotfiles)/$app
/var/www/$app/$env
/var/www/$env/$app

Priority is given to the homedir if $env is development or unspecified.

/var/www is also searched with $env = production if $env is unspecified.
Renames var from $name to $app
Fixes #16 - adds auto-git-clone to app() function