v0.4.0: bump minimum go version and update dependencies

Bump minimum go version to 1.19 and run `go mod -u` to update all
packages.

v0.3.0: Update README.md

Issues that are related to connection problems are mostly because of a faulty installation of your OPC automation wrapper or some peculiarties of your specific setup and OPC installation. Since we cannot debug your specific situation, these issues will be directly closed.

Fix #8 #12 #19