utils/json_generator library

1. flutter_workflow_builder package
2. documentation
3. utils/json_generator.dart

flutter_workflow_builder package

1. Libraries
2. flutter_workflow_builder
3. models/workflow_config
4. models/workflow_connection
5. models/workflow_node
6. painters/connection_painter
7. painters/grid_painter
8. utils/coordinate_transformer
9. utils/json_generator
10. widgets/workflow_canvas
11. widgets/workflow_json_preview
12. widgets/workflow_node_widget
13. widgets/workflow_properties_panel