Specify number of runs as an option for design table output & include base models

[GeoMattB]

Adding a "specfied number of experiments" to the minimal, best and optimal design tables generated would be useful. For example the best design table might be 300 experiments with minimum and optimal designs at 90, 100. However, the orthogonality and efficiencies on a 160 experiment set may be good enough, could improve the analysis and be efficient to run on specific hardware.

[GeoMattB]

Also, add ability to add "base model" to experiment design. Where a base case could be included in the design.
Essentially build the parameter pair sets but and option to always include a specific design. Some error checking would be needed to make sure the base case sat within continuous ranges.