gitview: Define __slots__ for Commit
gitview: Define __slots__ for Commit

Define __slots__ for the Commit class. This reserves space in each Commit
object for only the defined variables. On my system this reduces heap usage
when viewing a kernel repo by 12% ~= 55868 KB.

Signed-off-by: Michael Ellerman <17b9e1c64588c7fa6419b4d29dc1f4426279ba01@ellerman.id.au>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git