NEW/BREAKING: refactor CMake-Code, so static/dynamic switch is done via <code>BUILD_SHARED_LIBS</code>, which retires <code>JKQtPlotter_BUILD_STATIC_LIBS</code>, <code>JKQtPlotter_BUILD_SHARED_LIBS</code> and removes the capability to build static and shared libraries in one location (fixes issue #104)
NEW: prepareed library for CMake's <a href="https://cmake.org/cmake/help/latest/module/FetchContent.html">FetchContent</a>-API
NEW: the different sub-libraries JKQTPlotter, JKQTFastPlotter (DEPRECATED), JKQTMath, JKQTMathText can be activated/deactivated with CMake options JKQtPlotter_BUILD_LIB_JKQTPLOTTER, JKQtPlotter_BUILD_LIB_JKQTFASTPLOTTER, JKQtPlotter_BUILD_LIB_JKQTMATHTEXT, JKQtPlotter_BUILD_LIB_JKQTMATH
- improved: constructors and access functions for several geometric objects (e.g. more constructors, additional functions to retrieve parameters in diferent forms, iterators for polygons, ...)
- new: all geometric objects can either be drawn as graphic element (i.e. lines are straight line, even on non-linear axes), or as mathematical curve (i.e. on non-linear axes, lines become the appropriate curve representing the linear function, connecting the given start/end-points). The only exceptions are ellipses (and the derived arcs,pies,chords), which are always drawn as mathematical curves
- JKQTPGeoLine, JKQTPGeoPolyLines and JKQTPGeoInfiniteLine support decorators
- improved decorator drawing
- more decorator types
- improved example geometry
- added specific example geo_arrows
- improved documentation
- code cleanup
