Adds ruby 2.1.0 to the travis file and removes rbx-head.
Minor bug fixes and code cleanup.
Adds the ConfigProxy class.

This class is meant to make it easy to normalize config data without having to
mutate the state of the config objects.  It calls the normalize method for a
config option if it exists.
Adds the aws autoscale wrapper class.

This class uses the ruby aws SDK to and wraps the selected autoscaling group
with an interface that matches rivet's autoscale class.
Uses new common interface for autoscaling groups.  Shifts normalization to the config class

This commit shifts responsbility for normalizing data into the config class.
Instead of forcing the data to always be normalized in the config class itself,
there is a config proxy class which will check to see if a normalize method
exists and call it if it does.

Adds a fix for tags not being updated if there were removals.