gitweb: Add history and blame to git_difftree_body()

gitweb: Add history and blame to git_difftree_body()

Add blame and history to Deleted files.
Add blame and history to Modified or Type changed files.
Add blame and history to Renamed or Copied files.

This allows us to do
	blame->commit->blame->commit->blame->...
instead of
	blame->commit->file->blame->commit->file->blame->...
which is longer and easier to get wrong.

Signed-off-by: Luben Tuikov <redacted>
Signed-off-by: Junio C Hamano <redacted>