* FORTRAN extension for line elements has been ported to Python and `numba` (many thanks to Davíd Brakenhoff)
* Python `invlap` routine (again with numba) ported from routine by Kris Kuhlman (https://bitbucket.org/klkuhlm/invlap/src/default/)
* New `invlap` routine requires fewer terms in inverse Laplace transform (`M=10` is usually enough)
* Calibrate now works on ranges of parameters.
* Calibrate now adjusts `c` values between layers when calibrating for hydraulic conductivity in `Model3D`