remove detritus and worthless shell commands
clean up 2d-bindgen frontend based on defunct 2draw-bindgen
use K[ey]/V[alue] type names instead of S/T for GHashTable binding hack
work with rustc commit 5e1a69112584341522e2cc00bfc6dd1db6e0ec3a discriminant changes
add Makefile and document building/testing instructions; explain dependencies