First Catch2 tests for structural 1D elements

[jdeaton]

This PR is an extension of #60 and #70 and adds tests of existing MAST library capability related primarily to Structural 1D elements. Most tests were originally implemented by @JohnDN90.

Below is a checklist of commits implemented by @JohnDN90 in his add_catch2_tests branch the whose contents/functionality need rolled in. The checklist ones will be covered in this PR:

• Added catch2 header file for upcoming new tests. (#60)
• Bug fixes and enhancements to CMake files. (#60)
• Added option to use libmesh_devel (development) version. (#60)
• Added catch2 tests for some MAST base functions. (#60)
• Added catch2 test for TEMPERATURE boundary condition. (#70)
• Added catch2 tests for mast_boundary_condition_base (#70)
• Removed shear coefficient (kappa) from isotropic material. Added plane strain support to isotropic material. (#60)
• Added catch2 tests for mast_isotropic_material. (#60)
• Multiple changes to orthotropic material, including added plane strain support. (#60)
• Added catch2 tests for orthotropic_material_property_card. (#60)
• Moved shear coefficient (kappa) to 2D section card and added overloaded functions to 2D section card. (#60)
• Added catch2 tests for solid_2d_section_element_property_card. (#70)
• Added overloaded functions to isotropic 3D section property card. (#70)
• Added catch2 tests for isotropic_element_property_card_3D. (#70)
• Added new public release statement to README.
• Add overloaded functions to solid_1d_section_element_property_card. (#70)
• Formatting for README.md
• Multiple changes to 1d_solid_section_element_property_card. (#70)
• Added catch2 tests for solid_1d_section_element_property_card. (#70)
• [x] Added basic catch2 tests for generic 1D structural elements.
• [x] Fixed bug in GitHub Issue #41 where NO_BENDING incorrectly called TIMOSHENKO.
• [x] Added catch2 tests for 1D structural element with extension and torsion.
• Fixed bug in GitHub issue #43, where incorrect I value was being used for bending about y-axis. (#75)
• [x] Added many for tests for 1D structural 2-noded (edge2) element.
• Added generic catch2 tests for 2D structrual elements.
• Added many catch2 tests for 4-node quadrilaterial 2D element (quad4).
• UPDATE EXAMPLES MOVING KAPPA FROM MATERIAL TO SECTION CARD (#60)
• [x] Fixed bugs in catch2 tests which caused some to fail when run with a debug version of MAST.
• [x] Necessary tweak to tests for zero and negative eigenvalues.

[jdeaton]

@JohnDN90 Do the changes in src/elasticity/structural_element_1d.cpp in https://github.com/MASTmultiphysics/mast-multiphysics/pull/79/commits/7bcd22d909c23d664a80ce4ed41342405604ec00 above in lines 660-672 also close issue #40?

[jdeaton]

@JohnDN90 Previous commit message said something about "extension and torsion", but I didn't see anything related to torsion there. Just wanted to let you know in-case there was something you intended missing.