adding ability to language overrides, these are subsets of other languages that will only override certain properties. so lets say you have en-us, but you have a custom module where you want to replace the property "users = Users" with "users = People".  You can create a "en-US-People" language that will normalize with relation to "en-US" and will NOT create any .properties files, but will write the compiled typescript files accordingly.  The suffixes are passed into the normalizer and are configurable