Add option to create fixed/constrained bonds in HOOMD converter

[chrisjonesBSU]

Describe the behavior you would like added to GMSO
We can use hoomd.md.constrain.Distance to contrain bond-stretching (i.e., fixed bonds).

This could be triggered in gmso.core.bond.Bond and/or gmso.core.bond.BondType.

[chrisjonesBSU]

This will be a lot more straight forward to implement than the rigid body implementation, as all the constraint information lives in the snapshot. We won't have to populate the hoomd.md.constrain.Distance object with anything, or even create and return it.

One question is, do we pull the bond constraint values from the actual bond distances in the topology or from the force field? There are use cases for either. Maye we include a flag that sets this, or include some logic that handles it.