Catch NodeExistsError when creating new znodes

Signed-off-by: Raul Gutierrez S <rgs@itevenworks.net>
Rename abspath to resolve_path and have it expand '', '.' and '..'

Signed-off-by: Raul Gutierrez S <rgs@itevenworks.net>
Call resolve_path() before handing the path to exists()

Signed-off-by: Raul Gutierrez S <rgs@itevenworks.net>
Release version 0.94.0

Signed-off-by: Raul Gutierrez S <rgs@itevenworks.net>