Hello everyone, I am new to the Git community and would like to contribute. I noticed that there are no builtin patterns for the Verilog language in `userdiff.c`. Since I recently worked on a project involving Verilog, I decided to add support for it. Below is a summary of my changes: 1. Added Verilog builtin patterns to `userdiff.c`. 2. Updated the documentation to reflect the new patterns. If you have any suggestions or feedback, please let me know. I would greatly appreciate your guidance to avoid any mistakes or detours. Thank you very much! Best regards, Hao Chenming