Currently we construct the destination path and check whether
it exists. This could miss a connection profile with same
name in another directory.
If a config with same name is found we set it as the destination,
and ask the user for permission to overwrite. However, if the duplicate
is in the global_config_dir, the behaviour is not changed -- that is,
the config is imported with no further prompts.
Also fix the use of same buffer as destination and source in
swprintf(). It seems to work, but is not 'legal'.
Signed-off-by: Selva Nair <selva.nair@gmail.com>