- multiple fixes in the Tcl commands (especially regarding the interchange between True/false and 1/0 values)

- updated the help for all Tcl Commands
- in Tcl Shell, the 'help' command will add also a brief description for each command in the list

tclCommands/TclCommand.py

@@ -58,6 +58,8 @@ class TclCommand(object):
             raise TypeError('Expected FlatCAMApp, got %s.' % type(app))
 
         self.log = self.app.log
+        self.error_info = None
+        self.error = None
 
     def raise_tcl_error(self, text):
         """