Prepare for new 16.x release (rust-ethereum#253)

This PR just bumps the versions in Cargo.toml to v16.0.0 in preparation for a new release including Solidity error types.

Release v14.1.0

Version 14.0.0

update uint and ethereum-types (rust-ethereum#201)

Version 11.0.0

Update Cargo.lock

Merge pull request rust-ethereum#158 from paritytech/na-kill-try

use `?` instead of `try!`

Merge pull request rust-ethereum#159 from paritytech/IncreaseCratesVe…

…rsions

Versions of two other ethabi crates increased

Merge pull request rust-ethereum#155 from paritytech/dp/fix/edition-2018

Fix for use in edition 2018 crates

Merge branch 'master' into td-script-improve