+ add several fixes

~ fix a potential NPE in RedisTemplate
 ~ add JDK 1.5 source/target compatibility
 ~ fix type in documentation

docs/src/api/javadoc.options

@@ -1,11 +0,0 @@
--breakiterator 
--header "Spring Data Redis"
--source 1.6
--protected
--quiet
--docfilessubdirs
--group "Spring Data Redis Support" "org.springframework.data.redis*"
--link http://static.springframework.org/spring/docs/3.0.x/javadoc-api
--link http://download.oracle.com/javase/6/docs/api/
--exclude org.springframework.data.redis.config
-