Multiline secrets, tree updating, bug fixes

We're happy to release this new version. It primarily addresses issues that were reported by the community. Thanks for reporting them and using Gopass UI!
(In case you're wondering: please don't ask about v0.5.0, it went lost before the first coffee has been drunk.)

Features 💰

• Create and edit secrets with multiple lines of text no matter of their format (e.g. gopass create creates YAML like values). Fixes #29, #28
• The tree on the left side will now update in case secrets are added or deleted and also preserve its toggled nodes. Fixes #24
• Show secret values also if "safecontent" option is enabled. Fixes #30

Bugs fixed 🐞

• Password health does now give output if no password-like secrets were found to analyse. Fixes #34
• Closing the explorer and opening it again from the tray icon throws an error alert. Fixes #31