Merge pull request #14 from computerquip/autotools-fix

Minor change that fixes error message and sets a wxVersion variable
implement scene adding callbacks, make a few API tweaks
renamed some window files to ensure they sort a bit better
fixed project file settings for those renamed files and fixed a typo
Add ability to use two desktop audio devices at once in basic UI
added a SceneRemoved handler
added a name entry dialog to the form files
update callbacks for name dialog
added name dialog code, moved 'using namespace std;' out of headers and into source files
change obs_scene_destroy to obs_scene_release, add ability to add scenes, fix name dialog sizing
make sure another source by the same name doesn't already exist when choosing a name for that scene
make OK button the default button for when using the 'enter name' dialog
add static linking options for ffmpeg and wxwidgets to cmake
add newline to non-windows log output
update data files copy in cmake project
implement 'remove scene' button
fix advanced variables in ffmpeg cmake files
add support for static system GLEW to cmake
add form callbacks for selecting scenes/sources
make it so that when a scene is clicked it becomes active