Manage final user-input errors.

Remove unneeded code, fix minor potential issue with length.

Remove "unknown" from version string.

Include git commit date & hash.

Use proper version string.

Networking fixes

Fix potential deadlock on node table update

Squash more warnings

dev/test/build tools to separate crate

Back to original slab crate

Better user errors.

Conflicts:
	util/Cargo.toml
	util/src/lib.rs

UDP Discovery