Move Confd getCurrentTime to Utils

The Confd server implementation has a getCurrentTime function.
This commit moves it to the Utils.hs file of Confd, so that it will be
available to be used by the future Confd client as well.

Signed-off-by: Michele Tartara <mtartara@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>