Give PhutilRope and LinesOfALarge a couple new capabilities
Ref T10186. To fix that, I need to stream files out of commands like git cat directly into file storage.
This adds two capabilities to support this:
- LinesOfALarge can now just ignore delimiters and stream all the data directly.
- PhutilRope can now produce a prefix of a specific length (this is used to produce a chunk-sized prefix).
Test Plan: See next revision.
Reviewed By: chad
Maniphest Tasks: T10186
Differential Revision: https://secure.phabricator.com/D15071