- replaced the testing if instance of FlatCAMObj with testing the obj.kind attribute

- removed the import of the whole FlatCAMApp file only for the usage of GracefulException
- remove the import of FlatCAMApp and used alternate ways
- optimized the imports in some files
- moved the Bookmarksmanager and ToolDB classes into their own files
- solved some bugs that were not so visible in the Editors and HPGL parser
- split the FlatCAMObj file into multiple files located in the flatcamObjects folder and renamed the contained classes with names more suggestive
- updated the Google Translation for the German language

tclCommands/TclCommandOpenGerber.py

@@ -1,6 +1,5 @@
 from tclCommands.TclCommand import TclCommandSignaled
 from camlib import ParseError
-from FlatCAMObj import FlatCAMGerber
 
 import collections
 
@@ -53,8 +52,8 @@ class TclCommandOpenGerber(TclCommandSignaled):
         # How the object should be initialized
         def obj_init(gerber_obj, app_obj):
 
-            if not isinstance(gerber_obj, FlatCAMGerber):
-                self.raise_tcl_error('Expected FlatCAMGerber, got %s %s.' % (outname, type(gerber_obj)))
+            if gerber_obj.kind != 'gerber':
+                self.raise_tcl_error('Expected GerberObject, got %s %s.' % (outname, type(gerber_obj)))
 
             # Opening the file happens here
             try: