[Geany] Adding a new file type?

[Laszlo Nagy]

> Unless you are going to code it into Geany you need to make it a
> custom filetype, see
> http://www.geany.org/manual/current/index.html#custom-filetypes
Works like a charm. :-)

It would be cool to add a custom lexer, but I guess this would not be 
possible without C programming.

Is there a way to auto-build files? E.g. automatically run the build 
command after I save a file.