New Relic has changed the formats for recording Datastore metrics, and provided a public API in the agent (as of 3.11.0) that should be used to record those values. This commit updates newrelic-redis' instrumentation to use those API's. Additionally, this updates the required version of newrelic_rpm associated with newrelic-redis, as it relies on API's that only were added in 3.11.0.
A number of different methods which have been deprecated or removed were in use in the tests. This brings them up to date with the 3.11 agent practices we'd like. Further work to update to full Datastores support for New Relic will be built on top of this.
Log as info to be consistent with other instrumentation messages. The message "Installing Redis Instrumentation" is missing among the other messages because the default log level is info.