Bspline Fortran Versions Save

• Added a bspline_order_linear parameter
• Readme updates
• CI updates
• Test updates

• Fixed CMake project (the two new recently added files were not included).

• Initial implementation of dfc, which can be used to fit B-Splines to 1D data using a weighted least squares method, including equality and inequality constraints.

• Initial implementation of defc, which can be used to fit B-Splines to 1D data using a weighted least squares method.
• Fixed dummy argument intents in dbspvn. 🐞
• Fixed unit tests when compiling with real precision other than real64.

• CMake updates
• Fixed a minor issue preventing compilation with PGFORTRAN
• Some unit test updates and a bug fix

No code changes, just the build and CI system. FPM is now the main way to compile the library and run the tests.

• Removed fobis support
• Removed build.sh script
• Removed pyplot-fortran submodule. Now an FPM dependency for the tests.
• Removed tests from CMake project

• Changelog
• Added two new interfaces to db1ink, which allow some control of the boundary conditions at the endpoints. Currently, this only works for k=4 (3rd order) interpolation.
• Some upgrades to the CMake project.
• Added selectable real and integer kinds
• Added VSCode workspace file.
• Added Fortran Package Manager file.

• Various changes to allow for larger sized data sets without causing stack overflows:
  • The internal work arrays for the db*ink routines are now allocated. So they are on the heap rather than the stack.
  • For the db*val routines, the work arrays are now inout subroutine arguments. The user can choose to put them on the heap by making them allocatables.
  • The integer kind is now explicitly defined using the ip parameter. It is int32 by default. A user could change it to int64 to prevent overflows for large data sets.
• Removed potential stack overflows (caused by reshape functions) when compiling with the Intel fortran compiler for the db3ink and db5ink routines.
• Added the bspline-fortran logo to the ford-produced documentation.
• Removed some potential compile-time warnings.

Note that the object-oriented interface is unchanged, but the subroutine interface has changed (the db*val routines now include the various work arrays).

• Minor changes to remove some compiler warnings.

• Fixed a bug where extrapolation to the right didn't work for dimensions higher than one. 🐞
• Added two additional error message codes to get_status_message().
• Minor updates to readme, tests, and doc deployment.