Shake v0.17 released

[Neil Mitchell]

Hi all,

Shake v0.17 is out. I wrote a blog post at
https://neilmitchell.blogspot.com/2018/10/announcing-shake-017.html,
which outlines three major features:

* Better error messages
* A Database module for opening the Shake database and prodding it repeatedly
* Changes to BuiltinRule, which are the main backward incompatible pieces

Full changelog is at https://github.com/ndmitchell/shake/blob/master/CHANGES.txt

The two planned big ticket items for the next development cycle are:

* Cloud caching for Shake builds
* FilePattern library split out as a separate piece

Thanks, Neil