Replaced colours with a dark/light blue one.

Previous ones were not suitable (red/green), as they may have different
implications.
Don't need quotes with JSON.stringify().
Another too many quote....
Merge branch 'master' into confirm-button
Removed unnecessary console.log.
Hopefully made makeBooking() more likely to succeed. Needs testing.
Removed commented-out code and made sure ticker name is returned when making a booking.
Not booking two slots at one time should now actually work.
Logical error in showing wait toast.