Merge branch 'jg/status-config'

"git status" learned status.branch and status.short configuration
variables to use --branch and --short options by default (override
with --no-branch and --no-short options from the command line).

* jg/status-config:
status: introduce status.branch to enable --branch by default
status: introduce status.short to enable --short by default

diff --cc Documentation/config.txt
Simple merge

diff --cc builtin/commit.c
Simple merge