This changes make_lexer() so that it no longer generates a custom target
but instead attaches the generated files to an existing one (so the first
argument now is the name of an existing library or executable, and it needs
to come after the add_library/add_executable call).
The generated source is no longer listed in the project sources, as it is
added by the function. The files are generated in the build tree rather
than the source tree, and the directory is added to the include path for
the respective project as well as exported to projects linking against it.
Generated files in subdirectories are somewhat supported, but need to be
referenced with the same name as they were generated (i.e. including the
subdirectory name).
Fixes: lp:1831643
* https://bugs.launchpad.net/kicad/+bug/1831643
Fixes: lp:1832357
* https://bugs.launchpad.net/kicad/+bug/1832357
Fixes: lp:1833851
* https://bugs.launchpad.net/kicad/+bug/1833851
* TokenList2DsnLexer.cmake now wraps each token enum in its own namespace. It
also no longer setup of the "using" directive in the header file, which was
bad behavior. C++ enum values will have name collisions unless the enums
themselves are different namespaces.
++new:
* Sweet library is now a DSO/DLL.
* Brought in SWIG to do a wrap of the Sweet DSO/DLL for unit testing
and scripting. The SWIG DSO/DLLs are built separate from the Sweet DSO/DLL
and are also optional.