Implemented -scanForPeripheralsWithServices:options:
Set up specta and expecta

Wow, much complicated.
Make sure calls to the manager are serialized properly

Ref: https://twitter.com/RenaudLienhart/status/438827343608426497
lol XCTest
Scanning test for RBTCentralManager

Test to make sure that existing signals complete when the scanning
parameters are replaced.
Update queue and scheduler name
Subscribe to delegate signal after scan has initiated
Remove stray brackets
Use -subscribeOn: operator
Remove method prefix from signal name
Start scanning after subscription
Test calling with same options to make sure it doesn't compelte
Remove explicit return type since its inferred
Local comment explaining the weirdness
Fix identation
Remove unnecessary CBQueue property
Follow signal naming conventions
Forgot a dash
Use _cmd instead of explicit selector name
Remove unnecessary NSStringFromClass()