Change md5sum/rust-crypto to deps/rust-crypto
Prevent rebuilding of up-to-date utilities
echo: check argument length when parsing options
Merge pull request #290 from kwantam/master

fmt: correct tab support, better formatting
seq: now passes about half of the Busybox tests
seq: handle --
Merge pull request #289 from Arcterus/gitmodules-update

Assorted fixes and improvements