Drag and Drop Replace tables in Query Builder

A new enhancement to replace a table with another one during Drag and Drop.

Example: Table A is already added in the Query Builder diagram and SQL is created. Now user can drag and drop another table B on top of A and it gets replaced. 

Still another use case is in the the different Decks. For e.g all columns of Table A [A.*] is added in SELECT deck. User drags and drops all columns from another table B from the Table node in top of A and it gets replaced and SQL is automatically generated. In current implementation, the Table gets added additionally and no replace function is available