Merge pull request #4 from phleet/jlfwong-remove-fi

Don't output fi= and cfi= lines
Merge pull request #5 from phleet/jlfwong-qcachegrind

Try qcachegrind if kcachegrind is not found
Update CONTRIBUTORS.txt
Merge pull request #6 from phleet/patch-1

Update CONTRIBUTORS.txt
Merge branch 'master' of https://github.com/pwaller/pyprof2calltree