THRIFT: Mutex and ReadWriteMutex leaked memory, now they don't

THRIFT: Mutex and ReadWriteMutex leaked memory, now they don't

Summary: also added myself to CONTRIBUTORS.

Reviewed By: marc

Test Plan: the following program no longer leaks memory (valgrind):

int main(int argc, char **argv){
  Mutex mu;
  mu.lock();
  mu.unlock();
}

Revert Plan: ok

Notes: this is kind of important

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665279 13f79535-47bb-0310-9956-ffa450edef68