Add element results to post module

[akaszynski]

This issue tracks adding element results to the post module.

• [x] U: X, Y, or Z structural displacement.
• [ ] ROT: X, Y, or Z structural rotation.
• [x] TEMP: Temperature.
• [ ] PRES: Pressure.
• [ ] VOLT: Electric potential.
• [ ] MAG: Magnetic scalar potential.
• [ ] V: X, Y, or Z fluid velocity.
• [ ] A: X, Y, or Z magnetic vector potential
• [ ] CONC: Concentration.
• [ ] CURR: Current.
• [ ] EMF: Electromotive force drop.
• [x] S: Component stress.
• [ ] EPEL: Component elastic strain.
• [ ] EPTH: Component thermal strain.
• [ ] EPPL: Component plastic strain.
• [ ] EPCR: Component creep strain.