obs-properties:  Add a few features

Just wanted the ability to be able to add private data to the properties
data.  Makes it a little easier to manage data if you get updates from
controls.
Make w32-pthreads and jansson shared libraries
util/darray.h: Fix astoundingly silly assert
libobs:  Add services API, reduce repeated code

Add API for streaming services.  The services API simplifies the
creation of custom service features and user interface.

Custom streaming services later on will be able to do things such as:

 - Be able to use service-specific APIs via modules, allowing a more
   direct means of communicating with the service and requesting or
   setting service-specific information

 - Get URL/stream key via other means of authentication such as OAuth,
   or be able to build custom URLs for services that require that sort
   of thing.

 - Query information (such as viewer count, chat, follower
   notifications, and other information)

 - Set channel information (such as current game, current channel title,
   activating commercials)

Also, I reduce some repeated code that was used for all libobs objects.
This includes the name of the object, the private data, settings, as
well as the signal and procedure handlers.

I also switched to using linked lists for the global object lists,
rather than using an array of pointers (you could say it was..
pointless.)  ..Anyway, the linked list info is also stored in the shared
context data structure.
Changed the windows test app a bit
Add 'common' and 'custom' RTMP services

This plugin is just a generic service plugin for basic RTMP streaming
service stuff.

This just has a 'common' service that has a list of common/simple
streaming services that don't have their own custom service modules, and
then a 'custom' service that allows you to enter in the stream URL and
key manually, without a service/server list.

Also, copy the jansson VS projects file (don't modify the old one) so
that it's located in the vs/2013 directory, so that other libraries can
properly link with it without having to enter in extra information just
to include jansson