Add ability for components to define configurables
use truncated stacktraces in rspec by default
Add class methods for components to define options

Component base classes get extended with ComponentOptions which gives
access to a limited version of Thor's DSL for defining command line
options. This is not yet wired in to the CLI, but it automatically
generates a component specific config class that can be used to "hard
code" defaults in a bootstrap definition file.
Extract chef-client-specific config generator code
Standardize on plural namespaces for components