Add first iteration of module saving task.
Store module path in session.
Implement default task executor.
Add saving support to the module object.
Add save button.
Set command line module path as the save target.
Rewrite task execution, disable UI when saving is in progress.
Move module loading and sandbox creation to the module model and root view.
Support token bouncing in the audio engine data setter.
Support flushing of transactions pending validation in store.
Flush store before saving.
Keep save button disabled until loading has finished.
Use save dialog when saving a new composition.
Clean up.
Always show the save button.
Fix variable access from an empty environment state.
Merge pull request #263 from kagu/fix_empty_env_state

Fix variable access from an empty environment state
Merge pull request #262 from kagu/save

Save
Add a centralised (incomplete) list of event descriptions.
Add generic field input support to the sheet.