Use Jedis rather than Lettuce

[wilkinsona]

Salvatore has indicated that Jedis is the Java Redis client of choice. Update the Redis auto-configuration accordingly

cc @christophstrobl

[dsyer]

I used Lettuce originally because that's what they had in XD. We might want them to know we did this (cc @mpollack, @markfisher).

[wilkinsona]

Sorry, Dave. I thought you were on the email discussion about this. In it @markpollack said:

We can move to Jedis for Spring XD … I'll schedule the issue to be resolved for the next XD release in 3 weeks

[markpollack]

This issue #850 looks like it would be a blocker for us to move off boot 1.0.2 release. I think we will upgrade our sprint boot dependency in our next next release then. Shifting into 'release mode' for XD ATM and nothing else seems to be driving us to upgrade.