Update the changelog

ChangeLog

@@ -1,5 +1,8 @@
  2021-??-??  Tyson Andre
     * twemproxy: version 0.5.0 release (dev)
+	  Add 'tcpkeepalive' pool boolean config flag setting
+	  to enable tcp keepalive (charsyam, manju)
+	  Support redis bitpos command (clark kang)
 	  Fix parsing of redis error response for error type with no space,
 	  add tests (tyson, tom dalton)
 	  Update integration tests, add C unit test suite for 'make check' (tyson)
@@ -11,6 +14,7 @@
 	  sharding requests to backend services to improve sharding performance
 	  and fix potential invalid memory access when all hosts were ejected
 	  from a pool. (tyson)
+	  Optimize performance of deletion of single redis keys (vincentve)
 	  Don't fragment memcache/redis get commands when they only have a single
 	  key (improves performance and error handling of single key case) (tyson)
 	  Don't let requests hang when there is a dns error when processing a
@@ -30,7 +34,7 @@
 	  Optimization: Skip hashing and choosing server index when a pool has
 	  exactly one server (tyson)
 	  Support memcache 'version' requests by proxying the request to a single
-	  backend memcache server. (tyson)
+	  backend memcache server to fetch the server version. (tyson)
 
  2015-22-06  Manju Rajashekhar  <[email protected]>
     * twemproxy: version 0.4.1 release
@@ -43,7 +47,6 @@
       implemented support for parsing fine grained redis error response
       remove redundant conditional judgement in rbtree deletion (leo ma)
       fix bug mset has invalid pair (charsyam)
-      fix bug mset has invalid pair (charsyam)
       temp fix a core on kqueue (idning)
       support "touch" command for memcached (panmiaocai)
       fix redis parse rsp bug (charsyam)