refactor: file tree with systems defninitions refactored to limit ODR issues

Relates to #32 as with this commit we created something like modules for derived quantities

test/unit_test/runtime/digital_info_test.cpp

@@ -20,7 +20,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-#include <units/data/information.h>
+#include <units/data/data.h>
 #include <catch2/catch.hpp>
 #include <sstream>