Improved error handling for Android and iOS.

Updated FireAuth docs.
Added missing "linkWithTwitterCredential" method.
Updated deprecated API "fetchProvidersForEmail" to "fetchSignInMethodsForEmail".
Added "unlinkCredential".
Updated Changelog.
Fix testing issues.
Fixed formatting.

Add Github support thanks to @filleduchaos.

Author: slightfoot

packages/firebase_auth/CHANGELOG.md

@@ -1,3 +1,12 @@
+## 0.6.1
+
+* `FirebaseAuth` and `FirebaseUser` are now fully documented.
+* `PlatformExceptions` now report error codes as stated in docs.
+* Added support for `linkWithTwitterCredential` in `FirebaseAuth`.
+* Added support for GitHub to `FirebaseAuth`.
+* **Breaking Change** Renamed `fetchProvidersForEmail` to its new name `fetchSignInMethodsForEmail`.
+* Credentials can now be unlinked from Accounts with new methods on `FirebaseUser`.
+
 ## 0.6.0
 
 * Added support for `updatePassword` in `FirebaseUser`.