Revisit character network

[zkovari]

• add character
• draw connector line
• alt reveal
• common connection api
• extract event handlers from scene
• extract selection rect
• extract placeholder socket
• enlarge socket on hover
• block connecting to itself
• extract common socket func
• update connectors on move
• fix screen jumping on add
• new socket instance on link
• fix source socket position while link mode
• arrow for dest
• better connector shapes
• scene tooltip in addition mode
• proper escape addition
• connector editor
  • width
  • type
  • relation
• restore connector editor on selection
• turn relation selector to a menu
• more relation types
  • broken heart
  • coworker/professional/business
  • enemies/adversaries
  • alliance
• color selector
• icon selector
• reflect icon and color in editor
• change back default view