Grafting: Prevent any scripts from interrupting grafting

[alainbryden]

Recently, work-for-factions.js was fixed to never interrupt grafting ( #389 ), which is the main concern - but there are still other spots in the code where we might steal focus:

• daemon.js can decide to study at startup (universityCourse)
• ascend.js will stop any action in progress to avoid money being spent while it runs. (It should refuse to run if we're grafting)
• autopilot.js will attempt to:
  • stop any action in progress to run casino.js
  • run ascend.js when it thinks it's ready (without regard for grafting in progress.)
• bladeburner.js generally avoids interrupting player actions, but will interrupt if --ignore-busy-status is true. Grafting should be an exception to this and never interrupted.