Clarify wording.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13541 a5019735-40e9-0310-863c-91ae7b9d1cf9
Update list of ignored files.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13542 a5019735-40e9-0310-863c-91ae7b9d1cf9