* Add compare method to COLOR4D object.
* Add unit test to validate COLOR4D comparison method.
* Add missing color test in text attribute comparison method.
* Add unit test for text attribute object.
* Remove unnecessary headers from text attribute header.
* Move text attribute code into separate source file.
While convoluted, this model matches as best we have found so far, the
alignment with scintilla. The spacing is character size for N-1 of the
characters in the 4-space tab stops. The final character is sized for
the actual space character in the stroke font (0.761905)
Fixes https://gitlab.com/kicad/code/kicad/issues/13791
Allows placing parts from an external database that reference symbols from another loaded library.
Includes:
- nanodbc wrapper
- database schematic library plugin
- basic tests
Fixes https://gitlab.com/kicad/code/kicad/-/issues/7436