Create sidechain ports when created from template (#0007680)

Create sidechain ports when created from template (#0007680)

When a route with a sidechain is created from a template or by route
duplication the number of ports of the sidechain are set according to the
XMLNode defining the sidechain. Then the names are set according to the name of
the newly created route.

Thus all the pin connections defined in the template are replicated in the
newly created route.