When adding owner to collaborators file, add a newline to the end.

THis allows the owner to immediately begin adding collaborators on the next line.
Changed Save button to Save a Copy if you are not the owner.

Open the copied file in a new window. We don't open the copied file in the same window so as to not disrupt the collaborating session.
Merge branch 'master' of https://github.com/nsthorat/rtc-pencilcode-site

Conflicts:
	site/top/src/editor-main.js