Merge & Branch Nodes

A workflow runs sequentially, and all the nodes (except Decision) support only a single incoming & outgoing branches/connectors.
In order to create parallel flows (which should execute irrespective of any conditions), a workflow designer should insert 'Branch' & 'Merge' nodes.
1. Branch: User can create multiple outgoing connectors/branches. This node has a single incoming connector/branch
2. Merge: User can create multiple incoming branches/connectors. This node has a single outgoing branch.
All the parallel paths must execute, in order to execute Merge node in the end.