feat(semantic-release): implement for this formula

* Based on `ssf-formula` (v0.3.0)
  - https://github.com/myii/ssf-formula/pull/5
* Unable to use `pillar.example` directly for testing
  - Used it as a basis for `test/salt/pillar/default.sls`
  - Brought useful changes back to `pillar.example`
* Fix: avoid `users/googleauth.sls` for `RedHat` & `Suse`
* Close #203

FORMULA

@@ -0,0 +1,9 @@
+name: users
+os: Debian, Ubuntu, Raspbian, RedHat, Fedora, CentOS, Suse, openSUSE, Gentoo, Funtoo, Arch, Manjaro, Alpine, FreeBSD, OpenBSD, Solaris, SmartOS, Windows, MacOS
+os_family: Debian, RedHat, Suse, Gentoo, Arch, Alpine, FreeBSD, OpenBSD, Solaris, Windows, MacOS
+version: 0.46.1
+release: 1
+minimum_version: 2017.7
+summary: users formula
+description: Formula to configure users via pillar
+top_level_dir: users