When refreshing the AvailableDevices list, it is important to set the
original resolution on any DisplayDevices that were previously available
to allow the RestoreResolution() method to work correctly.
The issue is that some display devices report a BitsPerPel value of 0.
It is not clear whether this is a bug in WinDisplayDevice.cs or some
strange windows issue. The implemented workaround adds an entry to the
debug log and hardcodes BitsPerPel to 32 whenever this condition is
encountered. More investigation required.
* Platform/MacOS/QuartzDisplayDeviceDriver.cs: Updated to use the new
DisplayDevice constructors.
* Platform/X11/X11XrandrDisplayDevice.cs: Query Xinerama for the exact
bounds of each display device, if available.
Use global X lock to protect from multithreaded access.
Removed OpenTK.Graphics.Glu class (reason: deprecated upstream; most functionality provided by OpenTK math; not compatible with OpenGL 3.0+.) OpenTK.Graphics.Glu can be accessed through OpenTK.Compatibility.
Added OpenGL|ES-specific ErrorHelper classes.
Moved OpenTK.Graphics.DisplayDevice and OpenTK.Graphics.DisplayResolution to the root OpenTK namespace (reason: their functionality is not specific and does not depend on OpenTK.Graphics).
Split Graphics*Exception classes into different files.
Made GraphicsErrorException public (reason: necessary for OpenTK.Compatibility).
