Port for macOS (#311)

* merged moonlight-mac with moonlight-ios

* reverted to the original project.pbxproj

* cleaned up the code, fixed lots of unnecessary code duplications

* multicontroller support (not tested)

* new class that can be used for further modularization of the MainFrameViewController

Moonlight macOS.xcodeproj/project.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "self:Moonlight macOS.xcodeproj">
+   </FileRef>
+</Workspace>