[Spaces] Images for spaces - refinements

## Actual behavior
(1) When uploading a image to a space - the original file size will be taken
This leads to performance problems

(2) When changing a image for a space the old image still is part of the hidden .space folder
This leads to wasting storage space

## Expected behavior
(1) When uploading an image the image can be cropped to the size needed. In addition the image will not be saved in full (original) resolution inside .space directory

(2) Hold only one image in the .space folder, delete the old one