Custom gate tool

Add a tool that is able to create a custom gate from an exported logic creation (this is dependent on #3). Inputs should be input gate connectors and outputs should be output gate connectors.

Start by reading issue #3, since this feature depends on its exported logic creation. Then trace how exported logic, input gate connectors, and output gate connectors are represented; done means a custom gate can be created from that export with the specified connectors.

Written by the indexing model from the issue text.