* drop support for high resolution images

* migrate image model fields width and height to float

* SVG images: store width and height in table

* fix #1216: mime-type when using dropzone

* drop quality and other parameters for PNG and SVG in thumb-filename

* fix #1216: mime-type when using dropzone

* Fix: SVG images don’t have an exif header

* Fix: SVG images don’t have an exif header

* do not check for file extension if MIME type is 'application/octet-stream'

* replace all occurences of force_text by force_str

* upgrade to work with nodejs version 14

* move towards templatetag thumbnail

* upgrade to work with nodejs version 14

* proceed with latest versions of npm and gulp

* downgrade phantom and request

* install gulp globally

* add gulp-util to dependencies

* pin nodejs to 14.15.0

* more tests in gulp ci

* try with older versions

* with these versions of node packages, CI runs locally

* remove hacks r...