Upgrade to support Swift 5.0 with Xcode 10.2.1

[fitsyu]

Hi!

Awesome project!
However the moment I found it, it was available in older swift version.

So here is the updated version of the project for who uses (the current) swift 5.0 and Xcode 10.2.1.

Thanks!

[polok]

Hi @fitsyu
Many thanks for your PR. I was going to update this library next month, so your work will be helpful!.
I will keep this ticket open till then.

Regards,

[fitsyu]

Hi @fitsyu
Many thanks for your PR. I was going to update this library next month, so your work will be helpful!.
I will keep this ticket open till then.

Regards,

Glad if it can be of help for this project.

I found a strange issue and monkey-patch it in the last commit.

So the last commit probably better just to drop it