Merge pull request #298 from wenshao/master

improve WallFilter
Merge pull request #299 from wenshao/master

improve WallFilter
Merge pull request #300 from wenshao/master

improve WallFilter
Merge pull request #301 from wenshao/master

0.2.17-SNAPSHOT
Merge pull request #302 from wenshao/master

improve WallFilter & merged from merlin-master
Merge pull request #305 from wenshao/master

improve wall fitler
Merge pull request #307 from wenshao/master

improve WallFilter
Merge pull request #309 from wenshao/master

improve sql parer
Merge pull request #311 from wenshao/master

improve sql parer
Merge pull request #313 from wenshao/master

improve SQL Parser
improve sql eval
Merge pull request #315 from cutedemons/master

improve sql eval
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' of https://github.com/wenshao/druid