ref: 823f53c861bb49aecc6104e0add39fc3b0729025
parent: f9978ed16476ca6d233a89669c62c798cdf9db9d
author: Bjørn Erik Pedersen <bjorn.erik.pedersen@gmail.com>
date: Mon Aug 26 15:12:41 EDT 2019
Add a set of image filters
With this you can do variants of this:
```
{{ $img := resources.Get "images/misc/3-jenny.jpg" }}
{{ $img := $img.Resize "300x" }}
{{ $g1 := $img.Filter images.Grayscale }}
{{ $g2 := $img | images.Filter (images.Saturate 30) (images.GaussianBlur 3) }}
```
Fixes #6255