Git 2.4.4

1. 888692b http: init and cleanup separately from http-walker by Tay Ray Chuan · 16 years ago
2. c13b263 Make walker.fetch_ref() take a struct ref. by Daniel Barkalow · 18 years ago
3. 9fc6440 Set proxy override with http_init() by Mike Hommey · 18 years ago
4. 30ae764 Modularize commit-walker by Daniel Barkalow · 18 years ago