Natalie can pause, restart, and stop the manticore run #2437

[sschriner]

What

Natalie can pause and restart manticore or stop the manticore run

AC

• Natalie can go to the tools menu and all states not running are moved to the pause list and all currently running states finish
• When Natalie attempts to pause all states a pop up dialog shows to confirm
• She can go to the tools menu and select restart to move all states from the pause list to the waiting list
• Natalie can select stop from the tools menu to
  • Forcefully kill all running states
  • Move waiting and paused states to error
  • Nothing happens to completed states
  • The timer is stopped
  • The UI remains open after this process is complete
• When Natalie attempts to stop all states a pop up dialog shows to confirm

From: https://github.com/trailofbits/manticore/issues/2437