fixed synchronization in sync and thread. Each time a new thread is scheduled, interrupts will be turned on again
fixed another prob in schedule
sanitized malloc in threads
Merge remote-tracking branch 'origin/ben_dev' into ralph_dev
added child_list to thread
Merge remote-tracking branch 'origin/ben_dev' into ralph_dev

Conflicts:
	src/userprog/process.c
implemented wait and kill. Failing a lot of tests though
fixed double space and lock issues. 40/76 failing currently