View controller support

0.0.4

Add view controller support to hierarchy and layout

Bug fixes

Changes

• Allow StandardView to be used as a base class
• Add inequality constraint support to layouts
• Add convenience horizontal attributes to column layout

Basic functionality

Added

• Some standard controls
• Styling infrastructure
• Combine Publishers

Initial Release

• ViewHierarchy type
• Layout type
• StandView as base class for using ViewHierarchy and Layout