Version in Cargo.toml not updated for 0.2.0 release

[nachog00]

The version in Cargo.toml is still 0.1.2, but we've tagged and released 0.2.0-rc.2.

This means zainod --version reports 0.1.2 instead of 0.2.0:

$ zainod --version
zainod 0.1.2

Root cause

The workspace version in Cargo.toml was never bumped when preparing the 0.2.0 release cycle.

Fix

Update the version in Cargo.toml to 0.2.0 and release as 0.2.0-rc.3.

Additional improvement

Consider printing the version on startup so operators can easily verify which version is running in logs.