v0.2.0

Overdue for a release (sorry about that).

Changelog:
- Add docker component (151fd8)
- Revamp last_login component (parse utmp directly) (05f9af)
- Add memory component for RAM and swap (8adbf1a)
- Support proxy for weather component's network request (d5bbe36)
- More small improvements

Complete documentation and other fixes

- Add configuration section of README (78ebd6c)
- Add different sorting methods to SSL certs (efd52e3 and rust-motd#4)
- Remove runtime dependencies curl (c50b9dd) and openssl (127e3e8)
- Other clean ups and improvements

Add README.md

Add README.md