Finish speed cap implementation

[ror3d]

Changed the speed cap max to 2GB. For that I added the uiSyncFixedInt function to utils.c

Fixed the implementation for the buffer so it is maxed at both number of messages and size of the buffer, to avoid bufferbloating. The macro ALLOW_SET_BUFFER_SIZE can be set to allow the user to select the size of the buffer. If left unchecked, a quarter of the speed per second is used (as per common practices).

The buffering/dropping was done for both inbound and outbound packets once it had started. Changed to a packet per packet model to allow for only one direction capping.

Fixed a crash when dropping packets because they weren't popped from the list.

[jagt]

Thanks a lot!
I'll try to integrate this into the next release when I got time.

[VAllens]

Is there any progress on this pull request?

[ror3d]

Definitely not from me, and it seems the files in the project haven't had any update in the last 3 years, so I wouldn't count on this happening anytime soon :)