`update` method for optmatch objects

[adamrauh]

More description and original issue here. Making a new thread here so that I can keep more detailed notes/comments to myself/whoever wants to see.

[adamrauh]

• Update FORTRAN code to utilize reduced costs
• Integrate useful changes from hinting branch on this fork into issue54 branch
• Add warm-start capabilities for problems only differing by function arguments
• Generate CS-satisfying price vectors for new units being added to a problem (if possible)
• Functionality to combine problems previously divided into subgroups
• Integrate new "fast comparison" features, if/when necessary