Strand Routing Commands

Strand routing commands are used to do the following:

(split_net) Operate on wide nets that have already been routed with the normal flow.
(strand_route) Route nets using multiple strands between pins.

To strand route nets, do the following:

(Optional) Identify the nets and create a net_strand group of those nets using create_group.
- For nets in a set, use
```
create_group -name s_groupName -type net_strand -set d_setObj
```
- To specify the nets by name, use
```
create_group -name s_groupName -type net_strand -net {s_netName…}
```
This step is required only if strand constraints will be used.
(optional) Create a constraint group containing strand routing constraints for the nets.
Route the nets using strand_route.