fix description for srandmember bugfix
Reading through the changelog I noticed that one of the items seemed to trail off mid-sentence. I assume this was meant to refer to and
* 2.10.6
* Various performance improvements. Thanks cjsimpson
- * Fixed a bug with SRANDMEMBER where
+ * Fixed a bug with SRANDMEMBER where the behavior for `number=0` did
+ not match the spec. Thanks Alex Wang
* Added HSTRLEN command. Thanks Alexander Putilin
* Added the TOUCH command. Thanks Anis Jonischkeit
* Remove unnecessary calls to the server when registering Lua scripts.
