Load SolarPILOT field performance error

[qualand]

Bug description:
If an user:

1. Generates a solar field
2. Saves the file
3. Closes SolarPILOT
4. Reopens SolarPILOT
5. Loads previous made file (in step 2)
6. Simulates performance
   The receiver flux profile generated in step 6 differs slightly to that if the user generates a solar field and simulates performance without the steps outlined above.

Benchmark difference: (using SP default parameter values)

Flux Profile when field is generated then simulated:

System Summary Table

Flux Profile generated using steps 1-6 above:

System Summary Table:

• Highlighted values are discrepancies between generate then simulate method above.