This fixes all errors reported by cppcheck #3745.
Merge pull request #3746 from NAThompson/cppcheck_clean_3745

Cppcheck clean 3745
Shear-band Mohr-Coulomb tests added.  Fixes #3731
Addition of larger sliding block contact tests as per issue #3742
Merge pull request #3750 from gambka/contact_tests_3742

Addition of larger sliding block contact tests as per issue #3742
Merge pull request #3748 from WilkAndy/mc_tests_3731

Shear-band Mohr-Coulomb tests added.  Fixes #3731