[DDF-456] Another attempt at switching to slf4j
DDF-456: Updated to bring in latest slf4j.

Allows use of more than 2 parameters.
Merge pull request #1 from mrmateo/DDF456again

DDF-456: Updated to bring in latest slf4j.
Merge pull request #3 from bradh/DDF456again

[DDF-456] Another attempt at switching to slf4j
Reviewed by: @mrmateo