5.1.0

• Bugfix: task completion block never called when not following redirects.
  @adurdin, #175
• Declare in the project settings that the library contains swift code.
  @rodericj, #173
• Adjusted parsing of Mocktail files to allow headers to start on line 4.
  @Ashton-W, #172
• Allows access to the HTTPBody of POST request when using NSURLSession
  (Wiki entry)
  @iosphere, #166 #180