Add "Init" to build system

I don't think it's exactly what zeffii wants, but it works beautifully.
"SHIFT+ALT+B" fires off 'initialize.ck" in the current directory,
regardless of which tab you're currently looking at. "CTRL+ALT+B" will
still kill, and "F4" will still take you to the file/line/char on error.
There's no error checking going on here; I don't know what happens if
files are in different places, or exactly what it is that ST thinks the
"current" directory is.