Only show iOS tasks on OSX
Asynchronous tasks everywhere
Clean up compile tasks
Add compile task as prereq of tintan:build

Reimplementing the original intent of:
https://github.com/vic/tintan/commit/9736c3c7b1b84a7ec059e23e11e9d0b175f3660e
Don't run compiler plugin if launched from tintan CLI or subprocess of compiler plugin
Run default task from compiler plugin and wait to finish