Scrawl-canvas graphical entity functionality

[introduction text]

Create and display graphical entitys

• Factory functions
• Entity and Group object considerations

Positioning entitys on the canvas display

• The lockTo attribute
• Absolute and relative positioning
• Position by reference

Styling entitys

• The entity State object
• Entity visibility
• The method attribute
• Entity scale
• Entity rotation

Interactive entitys

[introduction]

Link zones

• Anchor objects

Action zones

• Button objects

Entity drag-and-drop

[TODO]

Accessible entitys

[TODO]

Keyboard accessibility

[TODO]

Form controls

[TODO]