Merge pull request #43 from runfriends/master

fixed a bug and optimized in MyCATSequenceProcessor
primaryKey与partitionKey都存在时，insert路由错误。测试表<table name="travelrecord" autoIncrement="true" primaryKey="ID" dataNode="dn1,dn2,dn3" rule="auto-sharding-long" />
as required by leader, i changed single thread pool into a wild thead in MyCATSequnceProcessor, just like before