Parameter Optimization Updates

[SteveMaas1978]

The documentation for parameter optimization is out of date with the current version of FEBio.
The documentation in the FEBio manual is for version 2.0.

Other useful features:

1. the print output format is "data point id,current value, required value, difference". It would be helpful if the simulation time was included in the output to more easily plot the data. Adding a log_level tag for only saving the final iteration to the log would also be helpful.
2. Data points are all weighted equally. It would be useful to include an option for weighting each data point within the point tag. Currently the user can effectively do this by repeating data points but a weight option would make it easier.