Merge branch 'jh/dirstat-lines'

* jh/dirstat-lines:
Mark dirstat error messages for translation
Improve error handling when parsing dirstat parameters
New --dirstat=lines mode, doing dirstat analysis based on diffstat
Allow specifying --dirstat cut-off percentage as a floating point number
Add config variable for specifying default --dirstat behavior
Refactor --dirstat parsing; deprecate --cumulative and --dirstat-by-file
Make --dirstat=0 output directories that contribute < 0.1% of changes
Add several testcases for --dirstat and friends

diff --cc Documentation/diff-options.txt
Simple merge

diff --cc diff.c
Simple merge

diff --cc diff.h
Simple merge