Remove string concatenation in slf4j logger calls.

This a good practice especially for debug logging since it avoids
constructing strings when the log level is disabled.
Merge branch 'slf4j-upgrade'

Conflicts:
	priam/src/main/java/com/netflix/priam/backup/RangeReadInputStream.java
	priam/src/main/java/com/netflix/priam/identity/DoubleRing.java
	priam/src/main/java/com/netflix/priam/scheduler/Task.java
Fix merge conflicts.
Make domain and region configurable for Simple DB instance data.
Merge branch 'sdb-config'

Conflicts:
	priam/src/main/java/com/netflix/priam/defaultimpl/PriamConfiguration.java