Merge branch 'maint'

* maint: Document accumulated fixes since 1.7.9.2 Git 1.7.8.5 grep -P: Fix matching ^ and $ am: don't infloop for an empty input file rebase -m: only call "notes copy" when rewritten exists and is non-empty git-p4: remove bash-ism in t9800 git-p4: remove bash-ism in t9809 git-p4: fix submit regression with clientSpec and subdir clone git-p4: set useClientSpec variable on initial clone Makefile: add thread-utils.h to LIB_H Conflicts: RelNotes t/t9809-git-p4-client-view.sh