Foreman Maintain

Update the satellite upgrade to new code

Extract control flow of upgrades to special file

Move sync-plans checks to pre/post migrations

Introduce run_strategy for scenarios

Health-check scenarios are better to run all steps regardless of errors
(:fail_slow strategy), while the migration scenarios should fail as soon
as first failure happens (:fail_fast strategy).

By default, the scenarios are treated as `:fail_fast`.

Full upgrade scenario

This commit intoroduces more structured upgrade scenario consisting of
this scenarios:

• pre_upgrade_check - non-modifying checks: is the system ready?
• pre_migrations - modifying procedures before source update
• migrations - source update and main migrations...

Hammer setup preparation step

Fixes #44 - Change tag 'basic' to 'default'

Run confine against classes, not objects

This allows us to have multiple objects of the same procedure in the
system, differing in the constructor parameters. Useful for parametrized
procedures.

Extract metadata DSL to separate namespace

Having the DSL methods directly on the classes caused issues when
needing to query the metadata later.

CLI basic structure