GUI exporting simulations to csv

[gtdang]

Add a button to export simulations to a csv file

• Simulations should have: time, L2, L5, and aggregate(L2 + L5) column.
• If multiple trials the file should be a wide format with L2, L5, and aggregate columns for each trial.
• There should be a mean of trials set as well (L2, L5, and aggregate)

Related to #709