Removing lingering references to LenardJones class

Cantherm was failing because it was still refering to LenardJones
class which is now removed after the transport branch has been merged.

Made the writing of output of measure also consistent to use
TransportModel
Fix to make standalone Cantherm work

Commit 5c4a2da0aec8e7abcc0153e4bfd62f84fe9f88d6 would
modify the label in the input file causing Cantherm to crash
when its trying to calculate kinetics for that reaction.
Molepro imported to canther statmech

The Cantherm example uses a molepro output file, leading to
a failure in the cantherm example. This change fixes the failure,
however there are possibly further fixes needed for correct
implementation in StatMechJob.
Unit tests for pickle use the highest protocol.

If we change some stuff to use __slots__ then this will be necessary.
In the mean time it should just make it faster.