Caches failed to clear, etc

It is a large dependency, that isn't needed for our use of node-fetch

Avoids circular imports

Moves repo picking utils to RepositoryPicker

Until this can be implemented properly

Adds types for comparison uri methods

Adds get previous line comparison uris for GitHub
Improves perf of get previous comparison uris for GitHub
Replaces HEAD usage with proper revision for GitHub
Renames comparison uri methods for clarity

Providers can now choose how to handle editor contents blaming
Simplies "commit" line model to just have line & originalLine
  - Not really accurate for log parsing, but close enough
Adds forces line blame to improve performance

In favor of the same options as buttons on the commit item itself

Moves scm git uri creation to local git provider
Removes relative path usages from GitUri
Adds commit.findFile overload for a uri

Adds separators to better group commands
Adds isPushed to commits

Moves formatting globals to the container

Adds authors filtering to commits