tools: engine-notifier accept special chars

Due to the way configuration was loaded in the bash script
special characters would create some unwanted behaviors.

Now the configuration file is read and the variables are added
using "declare" statement
It is expected that the config file is of the form key=value

Change-Id: I5e6419a225bd02edaf1db38a2025dee74761ddf2
Bug-Url: https://bugzilla.redhat.com/883301
Signed-off-by: Noam Slomianko <nslomian@redhat.com>