Update Site.java

setCycleRetryTimes的javadoc是这么说的:Set cycleRetryTimes times when download fail, 0 by default. Only work in RedisScheduler.
而通过查看源码发现似乎并没有做限制,即只能用于RedisScheduler. 故想问一下该javadoc是否过时了?
Merge pull request #159 from zhugw/patch-3

Update Site.java