Add json file icon
Extract interface for breakpoint manager
Add an interface for a breakpoint renderer
Add resources for breakpoint marks
Add gutter constants
Use Gutters constants in GutterAnnotationRenderer
Create an abstract implementation of embedded document
Set file on EmbeddedDocument
Implement breakpoint renderer
Add an interface for styling lines
Add a 'debug line' style
implement BreakpointManager
Add information on the gutter click event
Add a HasLineStyler interface
EditorWidget has a line styler
Add a BreakpointRenderer factory
Embedded editors implement HasBreakpointRenderer
Bind BreakpointRenderer and BreakpointManager
Editor widget extends HasGutterClickHandlers
Editor presenter handle gutter events