Create local build environment using rbenv and GNU make

[maaku]

This pull-request adds scripts to build a local environment for development, configured to match Github's environment as closely as possible.

Executing ./configure && make in the root directory will download rbenv, compile the most recently supported build of ruby (1.9.3-p194), and use bundler to install Jeckyll. Jeckyll and Liquid are pegged to match the versions used by Github Pages (0.11.0 and 2.2.2, respectfully).

Executing make run in the root directory will launch jeckyll --server, and make shell will launch an interactive irb session.

[groundh0g]

Moving Rakefile tasks to new v 0.6.0 release.