Aenea

• Prefixes boolean properties with is and makes String? properties consistent.
  • rx.hidden -> rx.isHidden
  • rx.enabled -> rx.isEnabled
    ...
    also ...
  • since rx.text has now type String? to be consistent with UIKit, in case String is needed
    there is rx.text.orEmpty that has String type.
• Renames title(controlState:) on UIButton to title(for:).
• All data structures are now internal (Bag, Queue, PriorityQueue ...)
• Improves performance of Bag.
• Polishes RxCocoa URLSession extensions
  • JSON -> json
  • return type is Any instead of AnyObject
  • replaces response tuple parameters, now it's (HTTPResponse, Data)
  • removes name hiding for request parameter
• Migrates Driver and NSNotification tests to Linux.
• Removes RxTest from OSX + SPM integration until usable XCTest support on OSX.
• Renames ObserverType.map to OberverType.mapObserver because of possible ambigutites with subjects.
• Improves dispatch queue detection logic and replaces concept of threads in favor of dispatch queues (solves a lot
  of problems on Linux environment).
• Replaces SectionedViewDataSourceType.model(_:) with SectionedViewDataSourceType.model(at:)
• Renames OSX to macOS across the project.

Anomalies

• Fixes wrong casing in #import "include/_RXObjCRuntime.h" (was creating issues for people with
  case sensitive file system). #949
• Fixes issues with locking strategy for subjects. #936
• Fixes code example in comments of RxTableViewExtensions that didn't compile. #947
• Adds .swift-version to help package managers to detect Swift 3 version.