UTC hardcoded in filename

UTC/Z is hardcoded:

ipfs-screencap/ipfs-screencap

Line 73 in e3209e3

name=screencap.$(date +"%Y-%m-%dT%H:%M:%SZ").png

This was shot at 20:48 UTC+2: https://ipfs.io/ipfs/QmWrTnB4qVcwFPuPPr6hqnkr2omrUbA1CU5tPxnXy7KR99/screencap.2015-09-19T20:48:12Z.png