Update CodeGenerator.scala

A generated class is overriding autoSession in trait SQLSyntaxSupport. 
I think override modifier is needed here.
Merge pull request #177 from hagikuratakeshi/patch-1

Update CodeGenerator.scala
1.7.2-SNAPSHOT
ConnectionPool.get(Any) should not return null but should throw exception when CP is absent
Added dynamic connection pool name & table name support
Removed dynamicSQLSyntaxSupport because it's a too easy way to be unsecure
Fixed #178 mappper-generator creates file that doesn't compile for table whose name is r*_s*
Fixed sbt plugin release script
Fixed test case
Changed joinWith(And|Or) appends round-brackets automatically and to(And|Or)ConditionOpt won't always append round-brackets
Removed broken and unused test
Added table name verifier (just warn logging)