Spec loader builds a spec representation.

A spec object is now created that holds the start of the abstract syntax
tree for a test specification. This is where Lucid's notion of a "test
spec" starts to merge with other tools' notion of a "feature file".

The original concept of a spec object (which was not part of the AST) has
now been recast as a spec file object.
Color module removed.

The color module was removed due to build #55 failing. This module was
quite a bit outdated and was failing on Ruby 2.1.0. Rather than attempt
to fix up what may simply be a poorly coded module, I will instead
revisit how to provide a coloring mechanism.