~shiny/gbcap

Fix readme formatting
Increase baud rate to 2Mbaud

This seems to be the fastest I can get to work.
Add uart test helper
Add license (MIT)
Make the number of lines to buffer a parameter

7 frames will just fit on my FPGA
Gameboy LCD capture module

Also reference VCD files from logic analyser and scripts for testing
Add simple UART echo module

For testing, just echoes back whatever is sent
Add UART module

Lightly modified core from LiteX. Removed some minor dependencies on the
rest of litex
Add migen submodule