Merge branch 'nd/builtin-to-libgit'

Code cleanups so that libgit.a does not depend on anything in the builtin/ directory. * nd/builtin-to-libgit: fetch-pack: move core code to libgit.a fetch-pack: remove global (static) configuration variable "args" send-pack: move core code to libgit.a Move setup_diff_pager to libgit.a Move print_commit_list to libgit.a Move estimate_bisect_steps to libgit.a Move try_merge_command and checkout_fast_forward to libgit.a