alternative valgrind-like support for run-tests along other nice additions

hi, It has been a long due request to have something similar to valgrind on Windows. I use a tool since quite some time for C projects and it becomes so handy that it is now a good choice for testing PHP as well, DrMemory (http://drmemory.org/) It works on many other platforms as well and provide some other tools and options that could be very handy for php as well. It uses their toolset called DynamoRIO (http://www.dynamorio.org/) which is amazingly powerful, brings strace for windows as well as many other niches tools. I made a quick port for run-tests.php -m using drmemory: https://gist.github.com/pierrejoye/e53deffb7e069a67fc3f (master). Draft stage, need cleanup of the log directory. Also willing to provide a PR to their repo to support --logfile valgrind options (will hopefully be discussed here https://github.com/DynamoRIO/drmemory/issues/1853). Be sure to have drmemory (1.9.x) in your path. This is only for Windows but I think it could make sense to provide it for other platforms as well, optionally. It can then allow us to support other features more easily. I am particularly interested to see if we can make some use of the fuzzy testing or use it to test our internals APIs (what we cruelly miss now). I did not test the performance but they claim to be faster than valgrind. If there is any interest I can continue the port and make it available on any supported platforms and create a RFC for it. If not, I will simply apply the windows port so windows devs (extension or core) can finally have something like valgrind. Thoughts, ideas and comments welcome. Cheers,