sbt/sbt — pull request #1147 by jsuereth (2014-03-04 16:39:19+00:00)
Title: Fixes #429 - Add better error messages when credentials are not found.

* Create hackery to inspect registered credentials in the IvyCredentialStore.
* Create a new authenticator which inserts itself *after* the ivy authenticator.
- Will issue an error message detailing host/realm required if credentials are
not found.
- Also lists out configured Realms with a 'is misspelled' message.
- Ignores proxy-related authentication errors, for now.

Fixes #429

Review by @cunei or @eed3si9n