This should be considered a blocker for backport to branch-1 since it will impact our compatibility.
The constants we expose in configuration should all start with "hbase". Since our configurations keys for the spark integration all relate to that system, the prefix for all configuration keys (excluding those cases where we need to do something special due to restrictions in how properties are handled by e.g. spark) should be "hbase.spark".
Before publishing a public api labeled version of our spark integration we should review all of our configuration keys to make sure they either conform to the "hbase.spark" prefix or they have a comment documenting why they need to be otherwise.