Logging update

[abelsiqueira]

• Solvers receive an option logger, and should log to that;
• solve_problem was removed because I don't think it was needed;
• solve_problems now has skipif, and also logger;
• solve_problems per iteration printing is "broken";

  • 75 is the required solution;

  • We lose real-time printing, because df = solve_problems(...) has all the information;
• Updated travis and appveyor

[coveralls]

Coverage decreased (-12.6%) to 57.771% when pulling 783d6e82d0940510c0480b4bd96985f6a4ab1904 on abelsiqueira:logging into b07674a39fc7310bfe307c7fa66db822db05f42d on JuliaSmoothOptimizers:master.

[dpo]

Great, thank you!