QT fakes a mouse move when destructing which is
caught by our filter

If the properties view changed in the properties window, the viewport of
the properties would not trigger a resize because the size of the window
itself does not change.  This creates a signal that allows the parent to
know whether or not to update a viewport, if any.

On OSX clicking the X title bar button immediately destroys "all" native
windows (after sending a close event) which causes
[NSSurface _disposeSurface] to crash if invoked while GL is using
the surface

Previously the properties window would sometimes not receive
a closeEvent, leaving a dangling pointer in OBSBasicMain (and resulting
in a crash when trying to open a new properties window or closing
the application)

 - Add a properties window for sources so that you can now actually edit
   the settings for sources.  Also, display the source by itself in the
   window (Note: not working on mac, and possibly not working on linux).

   When changing the settings for a source, it will call
   obs_source_update on that source when you have modified any values
   automatically.

 - Add a properties 'widget', eventually I want to turn this in to a
   regular nice properties view like you'd see in the designer, but
   right now it just uses a form layout in a QScrollArea with regular
   controls to display the properties.  It's clunky but works for the
   time being.

 - Make it so that swap chains and the main graphics subsystem will
   automatically use at least one backbuffer if none was specified

 - Fix bug where displays weren't added to the main display array

 - Make it so that you can get the properties of a source via the actual
   pointer of a source/encoder/output in addition to being able to look
   up properties via identifier.

 - When registering source types, check for required functions (wasn't
   doing it before).  getheight/getwidth should not be optional if it's
   a video source as well.

 - Add an RAII OBSObj wrapper to obs.hpp for non-reference-counted
   libobs pointers

 - Add an RAII OBSSignal wrapper to obs.hpp for libobs signals to
   automatically disconnect them on destruction

 - Move the "scale and center" calculation in window-basic-main.cpp to
   its own function and in its own source file

 - Add an 'update' callback to WASAPI audio sources

This function is inline, and QVariant uses a copy-on-write like copying mechanism, like most datatypes in Qt.

--------------------------------------------------
Notes and details
--------------------------------------------------
Why was this done?  Because wxWidgets was just lacking in many areas.  I
know wxWidgets is designed to be used with native controls, and that's
great, but wxWidgets just is not a feature-complete toolkit for
multiplatform applications.  It lacks in dialog editors, its code is
archaic and outdated, and I just feel frustrated every time I try to do
things with it.

Qt on the other hand..  I had to actually try Qt to realize how much
better it was as a toolkit.  They've got everything from dialog editors,
to an IDE, a debugger, build tools, just everything, and it's all
top-notch and highly maintained.  The focus of the toolkit is
application development, and they spend their time trying to help
people do exactly that:  make programs.  Great support, great tools,
and because of that, great toolkit.  I just didn't want to alienate any
developers by being stubborn about native widgets.

There *are* some things that are rather lackluster about it and design
choices I disagree with though.  For example, I realize that to have an
easy to use toolkit you have to have some level of code generation.
However, in my personal and humble opinion, moc just feels like a
terrible way to approach the problem.  Even now I feel like there are a
variety of ways you could handle code generation and automatic
management of things like that.  I don't like the idea of circumventing
the language itself like that.  It feels like one giant massive hack.

--------------------------------------------------
Things that aren't working properly:
--------------------------------------------------
 - Settings dialog is not implemented.  The dialog is complete but the
   code to handle the dialog hasn't been constructed yet.

 - There is a problem with using Qt widgets as a device target on
   windows, with at least OpenGL: if I have the preview widget
   automatically resize itself, it seems to cause some sort of video
   card failure that I don't understand.

 - Because of the above, resizing the preview widget has been disabled
   until I can figure out what's going on, so it's currently only a
   32x32 area.

 - Direct3D doesn't seem to render correctly either, seems that the
   viewport is messed up or something.  I'm sort of confused about
   what's going on with it.

 - The new main window seems to be triggering more race conditions than
   the wxWidgets main window dialog did.  I'm not entirely sure what's
   going on here, but this may just be existing race conditions within
   libobs itself that I just never spotted before (even though I tend to
   be very thorough with race conditions any time I use variables
   cross-thread)

add move constructor to wx connector class, add simple connector list class, add initial video settings class, update build files

fixed locale code, added locale files, made wx use locale files, fixed some bugs, and added platform-specific files to the main program

With the permission of my fellow contributors, I'm switching obs-studio back to GPL v2+ to prevent issues between this project and the original OBS project, and for personal reasons to avoid legal ambiguity (not political reasons, I admittedly would prefer GPL v3+)