- I've finally run the tests with OK result (56 tests in 102.937 sec)

- I had to play with module imports as they created a lot of error in
the tests although in reality the program worked OK.
- I've fixed some mistakes in TcL commands (they were testing isinstance
against the like of Geometry instead of FlatCAMGeometry)
- I've had to add some fixes in ObjectCollections.py (error on
create_index() method but Marco already fixed this in the checkbox
in project tab pull request and knew about this.
- Although at some point the tests run fine, I've made some checkings
on my own over the Tcl commands and discovered errors which I fixed as
mentioned above.
- conclusion is that tests are just a must and do not cover everything
(like saving projects which at some point by juggling with imports I
braked and tests were 100% OK)

tclCommands/TclCommandJoinExcellon.py

@@ -1,5 +1,4 @@
-from ObjectCollection import *
-from tclCommands.TclCommand import TclCommand
+from tclCommands.TclCommand import *
 
 
 class TclCommandJoinExcellon(TclCommand):