* allow repository config via cli
* make `helm repo add` create repo config file if it does not exist
* squash a ton of bugs
Signed-off-by: Adam Reese <adam@reese.io>
This flattens the getter package tree, adds tests, and changes a little
bit of the terminology to follow Go idioms. This also makes much of the
getter API private to begin with. This will give us more flexibility in
the future.