ignore Cabal sandbox directories by default

Cabal sandboxes are sandbox environments for Haskell packages,
containing compiled packages and a bunch of metadata that users of
ack are unlikely to want to search.  Therefore ignore .cabal-sandbox
directories by default.
Return config hash from _remove_redundancies on Windows
Colorize tests should expect backslashes in windows (gh #420)
Updated the locations of ackrc files on Windows
Merge pull request #426 from pdl/issue420

Colorize tests should expect backslashes in windows (gh #420)
Moved the windows slashifying into its own function
add a link to Design Guide
Merge pull request #401 from frasertweedale/feature/ignore-cabal-sandbox

ignore Cabal sandbox directories by default
Updating URLs for configs
Merge pull request #418 from jamessan/win-configfinder

Return config hash from _remove_redundancies on Windows
Thanks, James McCoy
Added filetypes for Jade, Smarty and Stylus
Use POSIX::mkfifo for portability
windows_slashify assigns, does not return a regex
Merge pull request #433 from pdl/issue420

windows_slashify assigns, does not return a regex
Releasing 2.13_03