todos
may fix winch bugs
might also be a good fix?
sigints working (perhaps too complicated)
fix up examples
testing window a little bit
rename Fmtstr.instert -> splice

It has slightly different semantics from JavaScript's array.splice,
but splice is the best word for it
important classes in main namespace
add simple example
fix curtsies keyname <Esc>-><ESC>
next planned feature