acu68229 Rename Hash and Array classes to not conflict with Core versions

This is needed so that clients can safely do the following:
    require 'rest_connection'
    include RestConnection::Rightscale
When the names of the custom classes are Hash and Array, they are not made available in the global namespace without the full module prefix because classes with the same name (the core versions of Hash and Array) already exist.
acu68229 Rename RightScale namespace to Rightscale