Upgrade all the things!
Switch to using RSpec's 'let' for fixture data.
Explicit tests for multiplicity.
Be more robust when inferring the attribute_name of a parameter.

Don't complain about the inability to infer an attribute_name, when
one has been explicitly provided.
Let's release that.
Clarify option inheritance (refer pull request 29).
Be more careful when passing option values into subcommands.

Specifically, Clamp will no longer inject an option value into a
subcommand that does not support that option.

Previously, there was potential to pollute the subcommand object
with unnecessary data, or worse, to accidently set instance variables
that were used differently in the subclass.
Provide a more complete "Quick Start" example.

Most importantly, highlight the need to call ".run" to make
things happen (closes #27).
Add tests for subcommand option inheritance

These are (failing) tests for subcommand option inheritance where the
subcommand is explicitly specified as a class rather than as a block.
Option inheritance currently fails when explicit classes are used to
construct the subcommand hierarcy.
Support option inheritance for subcommand classes

This implements support for option inheritance in the case of passing
a Clamp::Command subclass as a parameter to #subcommand, vs. as a block.

The key change is in subcommand/declaration.rb, with the rest largely
being fallout to make that work as expected.  Of note, Attributes now
persist any block they're given for later use when defining an attribute
writer method.