Merge branch 'rs/color-grep'

* rs/color-grep:
grep: prefer builtin over external one when coloring results
grep: cast printf %.*s "precision" argument explicitly to int
grep: add support for coloring with external greps
grep: color patterns in output
grep: add pmatch and eflags arguments to match_one_pattern()
grep: remove grep_opt argument from match_expr_eval()
grep: micro-optimize hit collection for AND nodes

diff --cc Documentation/config.txt
Simple merge