Release version 0.3.8
Changes since 0.3.6 includes:
- Make clippy happy with the code genarated for templates.
- Updated lazy_static to 1.0.
- Updated base64 to 0.8.
- Updated (optional) rsass to 0.6.
Tested with rustc 1.18.0 (03fc9d622 2017-06-06), 1.19.0 (0ade33941 2017-07-17), 1.20.0 (f3d6973f4 2017-08-27), 1.21.0 (3b72af97e 2017-10-09), 1.22.1 (05e2e1c41 2017-11-22), 1.23.0-beta.1 (082b0ff02 2017-11-21), and 1.24.0-nightly (5a2465e2b 2017-12-06)-