Merge branch 'mv/merge-custom'

* mv/merge-custom:
  t7606: fix custom merge test
  Fix "git-merge -s bogo" help text
  Update .gitignore to ignore git-help
  Builtin git-help.
  builtin-help: always load_command_list() in cmd_help()
  Add a second testcase for handling invalid strategies in git-merge
  Add a new test for using a custom merge strategy
  builtin-merge: allow using a custom strategy
  builtin-help: make some internal functions available to other builtins

Conflicts:
	help.c

diff --cc Makefile
Simple merge

diff --cc builtin-merge.c
Simple merge

diff --cc t/t7600-merge.sh
Simple merge