Added importance string to cell insertion functions and a variance reduction test.

v1.4.2

Add test for variance reduction.

Updated hexagonal lattice test to 3D.

v1.4.1

Added comment.

Added KCODE, KSRC, MTm cards with criticality example. Some function renaming.

v1.4.0

Updated after source changed.

v1.3.2

When printing cell summary, include material name. Also some minor cleanup to comments in the tests.

Tally energy list can also be given as an MCNP string using the i-notation.

v1.3.1

Create

SurfaceNum and CellNum are now classes instead of integers.

SurfaceNum now supports facets for macrobodies.

Added geometry elements and renamed some variables.

v1.2.0

Added geometry elements and renamed some variables.

Reorganizing order of functions.

Minor reorganizing, renaming some variables.

Support for material clone and some cleanup.

Add the ability to make a material clone with a different density.
Also ability to reserve some material numbers for manual use.

Latest version with cleaned docstrings and docs folder.

v1.1.1

Functions reordered and docstrings cleaned.