Create Twig Extensions for IIIF Image API IDs (and URL) and for JMESPATH evaluation

[DiegoPino]

What is this?

Two helper Twig extensions for our own need and users

• IIIF ID generator. Right now we are using our knowledge and data to build manually those IIIF Image API URLs. Used for IIIF manifests, Media serving, downloads, etc. That works and won't be deprecated but it would be easier if one could call a Twig Function with arguments that get that consistently generated.
• JMESPATH. Imagine you could get the list of PDFs that have more than 10 pages in a single call? Specially during manifest generation. Or all annotation with "comment" motivation. A simple wrapper function that also catches syntax errors and logs them instead of making user's life a hell would be great. E.g

"as:image".*|[?"dr:for"=='images' && "dr:mimetype"== 'image/jpeg' ]|[?"flv:exif".ImageWidth!='null']

Which will only fetch JPEGS uploaded to "images" where there is and actual ImageWidth

[DiegoPino]

This also opens solutions like

sort_by("as:image".*,&"sequence")[]|[?type=='Image']