All source files include general.h first and before anything else.
This inlcludes platform.h and platform_support.h
No header file needs to include to include any of these, but should include
any others needed for it's own declarations.
The introduction of the double buffering broke USB flow control, causing
loss of data when a new packet arrived with the previous still present in
the double buffer.
With this patch the endpoint is kept in NAK until the double buffer is empty.
