Add rdiscount

Fast markdown parser, useful with jekyll
pygments.rb also requires python2-pygments
Merge pull request #1 from jjk-jacky/pygments

pygments.rb also requires python2-pygments
Merge pull request #2 from jjk-jacky/rdiscount

Add rdiscount
Clarify config inheritance and rebuild_packages files
Specify license - GPLv3
Add gems popular at AUR
Allow to have recursive 'include' option

e.g. package config file can have 'ext/foo' and it works correctly now -
all directories in ext/ except ext/foo are deleted now.

We use spec.files list to find correct minimal set of directories to delete.
Instead of rsyncing whole repo into the chtoot, we just bind the index into chroot as read-only directory.
Leave bin folder in the package only in case if it contains registreted executables
Add more popular gems
Bash brace expansion requiers at least one comma (i.e. 2 elements)

handle the case of 1-element delete correctly.
Add foreman gem
Handle prerelease version in slot correctly
Add unparser to whitelist packages
Add octokit library
Use batch mode for gpg package signing, it is really silences the application
Add chefspec
More packages
Handle version bump for out-of-date dependencies correctly

Instead of having some weird heuristics on finding packages with out-of-date
dependencies just use straight algorithm - regenerate list of pacman dependencies
and check if it is the same as existing ones.

As bonus this also handles situations when dependency has changed via config file.