Merge branch 'master' of https://github.com/wdw1206/Mycat-Server
fixed NullPointerException on execution select next value for MYCATSEQ_XXX
Merge branch 'master' of https://github.com/MyCATApache/Mycat-Server
Merge pull request #49 from runfriends/master

FIXED NullPointerException on execution select next value for MYCATSEQ_XXXX