Revert "Edited greasefire icon a bit. Previous one used 2 gray scales, unlike the rest of your icons, and didn't resemble the original greasefire icon that much"

This reverts commit 74d6dbd1d3dca16b9b59fec0a2a5190146308102.
 Edited greasemonkey icon a bit. Previous one used 2 gray scales, unlike the rest of your icons, and didn't resemble the original greasemonkey icon that much