Fixing registration not letting simulator through

When I still get false positives about push notification registration. Not sure if this is because I don't have the production certificate, or if it's because my phone doesn't have a number (I use my actual phone's number and get the code that way), or if it's a mistake. Please check that out before merging.

- Added push notification registration exception for simulator
- Modified PushManager methods to return futures
- Renamed methods to include details like "shows alerts"
- Fixed the register view not progressing past number verification when alert verification fails
- Moved ios-version checks inside utility methods instead of having multiple utility methods with lots of high-level paths choosing which one to call