Naming issues

[elfilip]

VDB Builder prints confusing message when user creates an object with already existing name.
Example:
create-vdb aaa
VDB 'aaa' was created.
create-vdb aaa
'create-vdb aaa' command FAILED. javax.jcr.PathNotFoundException: No node exists at path '/tko:komodo/tko:workspace/aaa[2]' in workspace "komodoLocalWorkspace"

Also some of the object names should be forbidden. Mainly the objects with prefixes like tko: or tsql:. Commands usually can't handle such object names.