Improved cubic spline interpolation and slimmed interface for the extrapolation function in ISplines

Changes to the build system to link everything statically on windows and everything but boost statically on linux. Furthermore, Release is set as the default build type to reduce the size of the library.

Merge changes commited to 1-open-source-license into master

See merge request !6

Added compability for OpenSUSE 42.3 including cmake as low as 3.5.2 and fixed wording in license sections.

Resolve "Open source license"

Closes #7 and #1

See merge request !5

Added LGPLv3 information, added hykops_rudder to the build, merged splitted source files, removed obsolete files, and improved the makefile system for parallel builds on linux.

Closes #4 and #2

See merge request !4

The compilation and execution of libraries and binaries with shared and static libraries has succeeded on Windows 11, OpenSUSE 15.2 and Debian 11.

Closes #4

See merge request !3

Fixed order of additional options required for Windows and added an interface target to facilitate linking.

Adjusted further std::map::insert operations to comply with the logic from QMap, the code once was based on.

Erased std::map entries if a new one is to be inserted, because that is what QMap::insert does. Direct change to insert_or_assign is only possible staring from C++17.

Splitted implementation and defition of mapkeys, and ensure compilation of targets using HYKOPS with C++11 to 20.

Adjusted ranges for for-loops in lofttobsplinesurface to avoid segmenation faults caused by the original design while creating almost idential surfaces

Link HYKOPS library with Boost library, corrected ranges for the loops in AssembleFactory::lofttobsplinesurface and other fixes

Resolve: Change to CMake build system

See merge request !1

Configured CMakeLists.txt s.t. HYKOPS may be found with cmake in an external project using find_package(HYKOPS)

created a working cmake setup to compile hykops and added a Doxyfile for autogenerated documentation with doxygen

Freed hykops_propeller from Qt. The C interface has not yet been converted. Not tested but compiling.

Conforming parsing and serialization interfaces for the HYKOPS framework - but not yet thoroughly tested in every detail.