Release 1.5.0

This release includes multiple improvements related to error handling, and extensive overhauling of the documentation.

Special thanks to the contributors that made this release happen: @cjdcordeiro, @javierdelapuente, @jdkandersson, @sergiusens and @tigarmo

Full list of changes

• fix: switch from progress to message for init @sergiusens (#604)
• fix: 404 docs page @cjdcordeiro (#605)
• feat: add doc_slug to init @sergiusens (#603)
• fix: enable overlays in _enable_craft_parts_features() @tigarmo (#602)
• multiple error-related fixes @tigarmo (#601)
• fix: don't raise CraftValidationErrors in validators @tigarmo (#600)
• feat: create reusable setup instructions @cjdcordeiro (#599)
• Improve flask @javierdelapuente (#595)
• Flask docs @jdkandersson (#594)
• doc: add explanation and guide for "bases" @cjdcordeiro (#597)
• chore: point to temporary build dependencies @tigarmo (#596)
• feat: make 'license' an optional field @cjdcordeiro (#588)
• fix: delay enabling the overlay feature @tigarmo (#592)