Feature request: Logical objects

[nytamin]

Describe the solution you'd like
The Timeline-objects has a feature where they can be defined with "logical expresions" rather than time-based expressions.
Logical expressios can look like #objectId | #objectId or !.class + 5000

The Group playout-type should be possible to set to "logical" type, and when that happens, all Part in it will become "Logical Parts".

• Play/pause/stop on Group are removed
• Play/pause/stop buttons on Parts are replaced by a "enable/disable" toggle
• Parts can have one (or more) logical expressions

Also, other features we need to add are:

1. Be able to set classes on Parts and timeline-objects

A typical use case for this would be "when having Channel-logo. which should autimatically disappear whenever there's a commercial playing"