- Added new method 'available_config_sets' which returns and caches a list of
all the json set configs found in the 'config_dir' directory. This was added
to make it easier when you need to dump all the fixtures programatically.
+- Added method 'dump_config_sets' to let you dump more than one set at a time
+ more easily
- Added method 'dump_all_config_sets' which helps automate dumping all your
current config sets to a directory.