Icons in toolbox looks blurred on high resolution screens due to usage of PNG instead of SVG.
It was done because IE 11 didn't support some manipulations with SVG for more details see
RHPAM-433. Now we are not supporting IE 11 any more and we can revert this change and remove useless resource duplications.
PNG duplication icons are removed from the repository, and SVG originals used in for the toolbox icons.