Fix Linux compilation following addition of RenderFireworks

RenderSean.* was renamed to RenderFireworks.* so xLights.cbp.mak
needed to be regenerated.

Also apply several changes to the makefile generated by cbp2make
to cleanup compilation a little.

- Disable some compile warnings until the code they warn about is fixed.
- Change the destination of debug object files to a .objs_debug
  subdirectory to eliminate make warnings about "overriding recipe for
  target" and "ignoring old recipe for target".