floating was used as edgetype whilst floating wasn't available, ReactFlow automatically fell back to default. now it is changed to default in the code preventing potential unexpected behavior
ref: N25B-114
added a sidebar that supports drag and dropping new nodes from the sidebar into the flow editor.
also added a new package (neodrag) for easy draggable behavior outside the reactFlow editor.
ref: N25B-114
added a type for defaultNodeData, this can house common data that all nodes should have. the other types can build on this defaultData. Also added an endNode and phaseNode to NodeDefinitions.tsx, together with a nodeData type for each new node type.
ref: N25B-114
changed to startNode file to be a general file for custom node types, and created a custom type for the data property of StartNode.
BREAKING: renamed StartNode.tsx to NodeDefinitions.tsx
ref: N25B-114
