Fixes issue with CaptureTypes not being registered at the right time.

CaptureTypes were being registered by the editor providers, and that was
too late as they might have been needed before the editor providers are
created.

The fix involves the following changes:
 . Capture types are now extensions.
 . They don't need to be registered other than in the xml.
 . All the Capture-based editor providers have been removed in favor of
   a generic CaptureEditorProvider.

Change-Id: I9a6ddb39256328179475be58ea0459d8a0891cef
12 files changed