support kotlin

[uuidcode]

querydsl/querydsl#1828

I roughly wrote it.
I added test cases and verified kotlin compiling in many cases.
If this PR is acceptable, I think querydsl-maven-plugin and querydsl-codegen need to be changed.

I love querydsl and I hope querydsl will getting more popular.

thanks.

[Shredder121]

Ah thanks for spearheading this.
I have some experience writing Kotlin, but I'll have to read the spec before I can help out writing this.
The earliest that will be is this weekend, just so you know what to expect. 😉

[Shredder121]

Hi, I just wanted to say that in my opinion we could integrate Kotlin support in codegen more easily than Querydsl itself.
Since we'll have to integrate with tooling, we need proper documentation for language features, platform integration, etc.
I'll update the original issue with some comments regarding the situation.
Anyway, thanks again for starting on this, we appreciate it.