Merge branch 'mm/diff-renames-default'

The end-user facing Porcelain level commands like "diff" and "log" now enables the rename detection by default. * mm/diff-renames-default: diff: activate diff.renames by default log: introduce init_log_defaults() t: add tests for diff.renames (true/false/unset) t4001-diff-rename: wrap file creations in a test Documentation/diff-config: fix description of diff.renames