Update github.com/msteinert/pam to v2

[supertassu]

Hi, there's a new major version v2 of the https://github.com/msteinert/pam library used for PAM authentication. Please consider updating to it.

[tvrzna]

Hello, I assume, that it's related to the fact of not using thread unsafe finalizer and call transaction.End() on ownself. Or is there any other reason since PAM itself is dynamically linked?
I'll check changelogs and I'll try to update the library.

[tvrzna]

The update of library led to the dropping of support of older (< 1.20) Golang, which I initially wanted to avoid. However time goes forward and older versions of Golang are no longer supported more than 9 months now. At least it let me to remove usage of deprecated methods and directives.

[supertassu]

Thanks! Are you planning to do a new release with this or leaving that for later?

[tvrzna]

Not yet, no one reported any issue with older version of library, so I don't consider it as critical.

[supertassu]

Ok. A new release would be helpful since I need to update emptty in Debian so that I can update the golang-github-msteinert-pam Debian package to v2. Packaging a full release would be nicer but I can also just pull the last few commits from master to the package for now until there's a new tagged release.

[tvrzna]

Well, then it is a different story. I'll release emptty as v0.12.1.