Ruby 1.8.7 support for Aliases

Fixes error:
NoMethodError:
  undefined method `match' for :price:Symbol
  # ./spec/../lib/active_yaml/aliases.rb:23:in `initialize'
JRuby support

Fixes error:

Failure/Error: country = Country.create
     ActiveRecord::StatementInvalid:
       ActiveRecord::JDBCError: [SQLITE_ERROR] SQL error or missing database (near "DEFAULT": syntax error): INSERT INTO "countries" VALUES(DEFAULT)
     # ./spec/associations/associations_spec.rb:172:in `(root)'
Ruby 2.0 support in CI, requires Rails 3+