core: fix logging and mispelling in few classes

1.Fix mispelling of comment
2.Rephrase logging message
3.Log exception in error instead of debug
4.Getting the correct logger of same class in PasswordValueHelper
5.Not log same exception twice as error and debug, instead have one
unified logging in error for both message and corresponding exception

Change-Id: I1da28578bec13daa58e19081d78f6dbb07f264ca
Signed-off-by: Alissa Bonas <abonas@redhat.com>