[Lua]Add support for custom cameras and related sketchpad APIs

[TheGondos]

This PR adds support for D3D9 custom cameras. The gcCore API is hidden behind oapi calls to make usage straightforward :

• oapi.setup_customcamera
• oapi.delete_customcamera
• oapi.customcamera_overlay
• oapi.customcamera_onoff

The manual is updated and an example MFD has been added to the Lua Atlantis vessel (basically a simplified port of the GenericCamera from D3D9Client) Along with this, some new API has been added to support the GenericCamera port :

• oapi.clear_surface
• skp.copy_rect
• skp.stretch_rect
• skp.rotate_rect
• skp.quick_pen
• skp.quick_brush
• skp.get_surface
• skp.set_brightness
• skp.set_renderparam
• skp.set_worldtransform2d

[TheGondos]

gcGetCoreInterface was segfaulting during CTests in an fopen call when logging an initialization error, strange... Ended up lazy loading the gcCore when needed.

[TheGondos]

I'm done with this one, you can merge it if you feel it's ok