test: moved installed things into own dirs

I moved installed things into own dirs bin and lib.

@chriscool sorry to move things around again, the top level
test dir was getting a bit clutterd.
test/t0040-add-and-cat updated hashes (new random)
vendor: updated random + fixed test import

There is a dummy test import: test/lib/random-dep.go
Because godep doen't yet vendor binaries nicely.