Deleted duplicated method in cliutils.

Method import_class in cliutils duplicates method in importutils module,
and method import_versioned_module is more related to import tools,
so it is moved in appropriate module.

bp common-client-library-2

Change-Id: I7b8892b2885f8b05a8106300371481209e99749d
Merge "Deleted duplicated method in cliutils."