Image widget performance improvements

[teosarca]

Follow-up of metasfresh/metasfresh-webui-frontend-legacy#695

What is the current behavior?

Image widget it's quite slow. Some of the reasons were explained here: metasfresh/metasfresh-webui-frontend-legacy#695 (comment)

What is the expected or desired behavior?

Shall be fast :)

Ideas to improve on backend side:

• the image data shall not be stored in database (AD_Image table) but on filesystem in AD_Image record shall be just a descriptor.
• consider introducing width and height optional parameters to http://w101.metasfresh.com:8081/swagger-ui.html#!/image-rest-controller/getImageUsingGET endpoint. If specified, the backend shall resize/cache the image on given size.