Set ESC-to-meta timeout to 0 for vim keymap. Fixes #228.
Add -I5 to default rtsopts so that idle GC doesn't interfere with typing.
Get rid of the remaining boot files

Maybe we could get rid of some of the internal files now that we can
freely import from Yi.Types.

Things that should eventually happen:

* reduce number of orphans, some created by ripping out the types (easy
  ones moved)
* clean up Yi.Types so it's not just parts of 4 modules stitched
  together but something that can work together nicely