Wooden Train Track Connector, easy insert

Description from @ukaszDubczyk's original model:

This connector is meant for universal wooden train sets (It is not compatible with the Brio train track).

You can find here two types of connectors:

• snug fit on both ends (perfect to bridges & overhang tracks)
• one looser end (for common joints & corners)

I added slight chamfers to the main body and the grips to make it easier to insert the connector.