bug fixed for DruidStatService if wall filter not config
add license info & add testcase
Merge pull request #349 from cutedemons/master

sql wall visitor
Merge remote-tracking branch 'origin/master'
Merge pull request #350 from wenshao/47d4667b03e6d5f1d8280bd34826406f79eddfe3

bug fixed for DruidStatService if wall filter not config
Merge remote-tracking branch 'upstream/master'
refactor logging
bug fixed for concat
Merge pull request #353 from wenshao/master

request for bulk integrate
modify sqlwall rules
Merge remote-tracking branch 'upstream/master'