Update locked Rust dependencies:

 ^ bincode v1.2.0 -> v1.2.1
 ^ bindgen v0.49.2 -> v0.49.4
 ^ http v0.1.19 -> v0.1.21
 ^ libc v0.2.65 -> v0.2.66
 ^ lock_api v0.3.1 -> v0.3.2
 ^ mio v0.6.19 -> v0.6.21
 ^ num-traits v0.2.9 -> v0.2.10
 ^ openssl v0.10.25 -> v0.10.26
 ^ openssl-sys v0.9.52 -> v0.9.53
 ^ protobuf-convert v0.2.0 -> v0.2.1
 ^ rpassword v4.0.1 -> v4.0.3
 ^ security-framework v0.3.3 -> v0.3.4
 ^ serde_json v1.0.42 -> v1.0.44
 ^ signal-hook v0.1.11 -> v0.1.12
 ^ signal-hook-registry v1.1.1 -> v1.2.0
 ^ snow v0.6.1 -> v0.6.2
 ^ subtle v2.2.1 -> v2.2.2
 ^ syn v1.0.8 -> v1.0.11
 ^ tokio-executor v0.1.8 -> v0.1.9
 ^ tokio-reactor v0.1.10 -> v0.1.11
 ^ tokio-threadpool v0.1.16 -> v0.1.17
 ^ tokio-timer v0.2.11 -> v0.2.12
 ^ unicode-normalization v0.1.9 -> v0.1.11
 ^ unicode-width v0.1.6 -> v0.1.7
 ^ vcpkg v0.2.7 -> v0.2.8

Author: dmitry-timofeev