Set which files are inspected for TODO pattern

I've looked around quite a bit, but I can't seem to find the place where you tell IntelliJ which files to inspect for TODO items.  It does so in most expected places, but not all -- for example I'd like to be able to put todo's into comment blocks in jade files or handlebars templates or even just have a text file with todo's in it.  There must be a place where file types to inspect are mapped...