Go Systemd Versions Save

Changes:

• journal: add StderrIsJournalStream function
• internal/dlopen: fix test and run in CI

Changes:

• dbus: add Connected methods to check connections status
• dbus: add support for querying unit by PID
• dbus: implement support for cgroup freezer APIs
• journal: remove implicit initialization
• login1: add methods to get session/user properties
• login1: add context-aware ListSessions and ListUsers methods

Changes:

• dbus: fix deprecated marks and docs
• journal: close unix socket after successful probe

Changes:

• sdjournal: fix input argument type in C.Malloc call
• gomod: update godbus to v5.0.4

Changes:

• dbus: add KillUnitWithTarget
• dbus: fix typo in GetUnitTypePropertyContext
• sdjournal: drop conditional static specifier
• ci: clean up legacy helpers
• ci: let system settle before running tests

Changes:

• go-systemd: fix building on windows
• dbus: add context-aware methods
• dbus: add context to open functions
• dbus: add ListJobs method
• sdjournal: SeekTail should be followed by Previous, not Next
• sdjournal: add GetBootID support
• ci: add initial GitHub workflow
• ci: add container tests

Changes:

• docs: update docs links in README
• unit: do not export private constants
• unit: deserialize keeps all semantic data
• deserialize: Use quote to print possibly-invalid string
• login1: support getting active session and session details

Breaking changes:

• minimum Go toolchain version is now 1.12
• switched to Go modules, removed dep support
• switched to semver tags to appease Go mod

Changes:

• sdjournal: use internal dlopen package
• activation: fix tautological error handling

New features:

• import1: implement importd methods
• dbus: introduce GetAllProperties() for fetching all systemd unit properties
• machine1: add CreateMachine call (and variations)

Other changes in this release:

• sdjournal: provide errno codes in error messages as strings