Update: gh-47 : Binary Keys

[Joubin Houshyar]

long del(String ... keys) deletes one or more keys. Returned result
is the actual number of keys deleted. Same restrictions as mget
apply
regarding null/zero-length keys arg.

Fix for issue 47:
http://github.com/alphazero/jredis/issues#issue/47

Redis 2.2.n client.
branch: master
commit: 956a8749b67c41e988648cbdd335e2743fc92ce8

Notes: a very minor subset of commands (in JRedisFuture) and one
command in JRedis (RANDOMKEY) now return byte[] instead of String. At
this point, the client can't trivially determine if your key was a
generic byte[] or a String (UTF-8). But you do, so if you expect a
String, just do 'new String(returnedBytes);'.

This was o/c reflected in the broken tests, so that's the best place
to look to see note what you need to change (and how):

JRedis:
https://github.com/alphazero/jredis/commit/956a8749b67c41e988648cbdd335e2743fc92ce8#diff-18

JRedisFuture:
https://github.com/alphazero/jredis/commit/956a8749b67c41e988648cbdd335e2743fc92ce8#diff-17

Let me know if there are any issues.

/R