C# signal scripting

For complex signal systems, working with the SIGSCR file is not ideal due to its limited syntax. Using a C# scripting interface allows the use of structures that make the development easier, such as functions and enums. Additionally, a common script can be shared between signals, providing additional features through inheritance.

The API functions available for the C# scripts are the same as the SIGSCR functions, so both script systems can be used equally.

Two extra API features have been included:
- A string that is shared with other signals, as well as TCS scripts, which extends the MSTS integer aspect
- A function that allows sending messages between signals