v0.3.1

Update dependencies

v0.3.0

* Switch async runtime from `async-std` to `tokio`
* Update dependencies

v0.2.0

* Spread scanning to multiple hosts instead of trying to scan all ports
  on single hosts. Number of hosts to scan at the same time can be
  controlled with --concurrent-hosts parameter.
* Randomize the order of ports (and hosts) when scanning.
* Remove duplicates from port ranges.

v0.1.0

Initial release