use mio_serial repo using serialport-rs 2.0.0

[ndusart]

Following berkowski/mio-serial#1, it uses the new error type from mio-serial.

I removed mio dependency as it is not used directly in this crate.

[berkowski]

Once we get berkowski/mio-serial#1 into it's own branch I'd like to do the same here. You can adjust the dependency target in Cargo.toml accordingly to see how things build against the branched mio-serial, and we can track upstream fixes until things are ready to merge back into master.

[berkowski]

Please change to mio-serial = { git = "https://github.com/berkowski/mio-serial", branch = "serialport-2" }

[berkowski]

Please switch PR target to the new serialport-2 branch and update the mio-serial dependency to point at the similarly named branch. Should get some better test results.

[ndusart]

Branches are moved to serialport-2.

Tests are better, it's just errors from mio-serial bubbling up here.

[Susurrus]

serialport-rs 2.0 was just released.

[berkowski]

Yup! Moving forward this week when I've got time.

[berkowski]

Merging now that serialport-2 branch for mio-serial has been merged to master.