Checklist test sets

[tmigot]

It would be great to complete the list of test sets for nlp and nls problems.
The checklist of current sets for NLPModels:

• unconstrained problems (5 problems);
• bound-constrained problems (6 problems);
• equality-constrained problems (6 problems);
• bound and equality-constrained problems:
• inequality-constrained problems;
• mixed problems.

The checklist of current sets for NLSModels:

• unconstrained problems (6 problems);
• bound-constrained problems (7 problems);
• equality-constrained problems (9 problems);
• bound and equality-constrained problems:
• inequality-constrained problems;
• mixed problems.