The featureflag package gives other parts of Juju the ability to easily check to see if a feature flag has been defined. Feature flags give the Juju developers a way to add new commands or features to Juju but hide them from the general user-base while things are still in development.
Feature flags are defined through environment variables, and the value is comma separated.
# this defines two flags: "special" and "magic" export JUJU_SOME_ENV_VAR=special,magic
The feature flags should be read and identified at program initialisation time using an init function. This function should call the `SetFlagsFromEnvironment` or the `SetFlagsFromRegistry` function.