Fix view_menu

There were several issues with the view_menu icon:
- The checked in SVG files were not matching the PNG files which have
  been used so far.
- The disabled PNGs were not actually disabled, but copies of the
  enabled ones.
- A @2x.png icon was still the old chevron icon.

Fix:
- Use SVG file from
  eclipse-platform/eclipse.platform.ui#2995,
  clean up metadata and exactly align on pixel boundaries
  and (half) integer stroke width.
- Delete disabled SVG files and let the renderer derive the disabled
  PNG files.
- Re-render everything to PNG.

Author: sratz