3.0.0-beta.3

Added

• Support for LinkFactory to return null in order to not create an ongoing link
• Support for free links (no source/target required)
• PositionAnchor which reprensents a simple plain position (mutable)
• ArrowHeadControl to control a link's Source/Target on the fly
• attached css class to attached links

Changed

• Replace OngoingPosition with the new PositionAnchor
  • BaseLinkModel.Target will never be null anymore. An ongoing link will have a position anchor as the target
• Links.Factory signature now takes the diagram, source (model) and the target anchor
• Move DynamicAnchor back to Anchors namespace and seal all Anchor classes

Fixed

• Links attached to links not refreshing when the others are
• LinkPathPositionProvider not working with maxlength ratios
• Deleting a link not deleting the links attached to it

Removed

• PositionProvider argument from ExecutableControl for more freedom
• Id and Refresh from ILinkable
• Unused Offset from Anchor and make Model nullable