Add an easy way to define your own interpreter

[iongion]

I got the information on IRC, but I have since lost the chat message due to a computer crash These would be awesome:

1. Update documentation on how to do it
2. Provide a starting template
3. UI to be able to define your own interpreter

[moteus]

May be also add example of how to add not Lua interpreter. E.g. I want add ability to run perl scripts. (not debug but just run)

Update I update my plugin to be able add external interpreters to run srpts