seratch/scalikejdbc — pull request #167 by gakuzzzz (2013-11-03 00:42:23+00:00)
Title: Made dynamic join enable

It makes join query dynamic like `and` or where

```
case class Programmer(...)
case class Skill(...)

val (name, skill) = (Some("seratch"), Some("Scala"))

select.from(Programmer as p)
.innerJoin(skill.map(_ => SkillProgrammer as sp)).on(p.id, sp.programmerId)
.innerJoin(skill.map(_ => Skill as s).on(s.id, sp.skillId)
.where(sqls.toAndConditionOpt(
name.map(sqls.eq(p.name, _)),
skill.map(sqls.eq(s.name, _))
))
```