Script logging should show currently executing script and procedure name

[darkf]

This would make it much easier to track down scripting issues.

[darkf]

a71e118 makes it so that warnings show the script name, if given by the warn call.

I'd like the currently executing procedure name as well, but it requires either having a separate call stack for procedure names (properly pushed/popped with call/ret opcodes) or setting the current proedure name on call opcodes and reading the address stack for return values and mapping them to procedure names.

If this ends up being too involved, it's fine to drop it and just use the script name.