Update README.md to fix link to rust website

the rust-lang.org site requires www and doesn't redirect.
Merge pull request #358 from Arcterus/test-fix

test: fix build
Force programs to rebuild when a dependency changes
Update for lastest Rust
Merge pull request #360 from Arcterus/makefile-fixes

Force programs to rebuild when a dependency changes
Add tsort

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
Merge pull request #361 from akiradeveloper/feature/add-tsort-v2

Add tsort
Remove tsort from to-do list
Add stripping and LTO options to Makefile
hashsum: fix build
Merge pull request #363 from ebfe/hashsum

hashsum: fix build
Merge pull request #362 from Arcterus/lto

Add stripping and LTO options to Makefile
Move all of the utils into src
Merge pull request #366 from Arcterus/src-uutils

Move all of the utils into src
Move tests out of src and into test
Implement timeout (resolves #364)
Merge pull request #367 from Arcterus/src-to-test

Move tests out of src and into test
Merge pull request #368 from Arcterus/timeout

Implement timeout
Fix more bugs to pass Busybox tests
Merge pull request #369 from Arcterus/busybox-fixes

Fix more bugs to pass Busybox tests