Callgrind manual: rewriting start of section about avoding cycles

This hopefully makes the whole issue with cycles easier to understand.
And no, this does not get rid of the description of cycles, carefully
crafted by Julian ;-)


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@6747 a5019735-40e9-0310-863c-91ae7b9d1cf9
1 file changed