- Collapse transparency mask by default
- Add transparency mask: option to add or flatten mask
- Removed Use selection as mask
- Mask adding logic sets top paintlayer as active
- Fixes#91
- FIxes#85
interface update doesnt seem to register on fresh install
i.e., config files deleted. although other signal handlers
seem to work. changing to using lambda fixed it, but
idk why. as a precaution, more things use lambda now.