Build the project and verify the executable exists.

def make_project(self, executable, target):
        """Build the project and verify the executable exists."""
        command = 'make -f ../Makefile -C {0} {1}'.format(SRC_PATH, target)
        pipe = Popen(command, shell=True, stdout=PIPE, stderr=STDOUT,
                     env=CHILD_ENV)
        output = pipe.communicate()[0]
        if pipe.returncode != 0:
            raise MakeFailed(output)
        if not os.path.isfile(os.path.join(SRC_PATH, executable)):
            raise NonexistentExecutable(output)
        return output