Convenience feature for snapshots: Add "Reverse" or "Unmute" checkbox for mute target

[helgoboss]

"Unmute" is a quite popular use case because it's used to save CPU power. While one can use "Reverse" in the Glue section, it's not usable for snapshot loading with default values, which changes the target directly.

[helgoboss]

Potentially useful for other on/off targets as well - whenever the "Glue" section is skipped:

1. Target "ReaLearn: Load mapping snapshot": Relevant for the default value
2. Target "ReaLearn: Navigate within group"

• Mmh, but the "Glue" section is not completely skipped, target min/max is taken into account!

3. Group interaction with "Same target value" or "Inverse target value"

• Okay, but there's the alternative "Same control" or "Inverse control" already ... so there's no real benefit there.

So ... one way would be to change behavior a bit and respect the "Reverse" setting for 1 and 2. I prefer that. Existing users are unlikely to be affected because:

• "ReaLearn: Load mapping snapshot" with real memorized snapshots is brand-new and rarely used. It's also only relevant for snapshot targets with default value that don't cover all matching mappings.
• "ReaLearn: Navigate within group" exists longer, but it's unlikely that users assign the navigated mappings also to sources AND have the reverse checkbox checked.

[helgoboss]

1 (load mapping snapshot respecting reverse) is now implemented. It's applied to the default value only. Existing snapshots of the mapping are unaffected (which is important for backwards compatibility).

2 (group interaction respecting reverse) has been implemented in commit b10cb8a already.