[storm-redis] Upgrade Jedis to 2.7.0

Jedis 2.6.2 and 2.7.0 released just now.

It contains some bug fixes, applies tiny optimization, and adds some commands which are missing.

• 2.6.3: https://github.com/xetorthio/jedis/issues?q=milestone%3A2.6.3+is%3Aclosed
• 2.7.0: https://github.com/xetorthio/jedis/issues?q=milestone%3A2.7.0+is%3Aclosed