Remove RFN

[davelab6]

I suggest changing the copyright notice to

Copyright (c) 2002-2015 Coji Morishita 森下浩司 (co@underforest.com)

and making the license file otherwise the same as https://github.com/google/fonts/blob/master/ofl/hind/OFL.txt including filename

[rayshan]

Closed by bed5ec7

The reason I left RFN in there is because some fonts currently in the Google Fonts repo also have that, e.g.: https://github.com/google/fonts/blob/master/ofl/lato/OFL.txt

[davelab6]

Yeah I discourage it, it is grandfathered in to some families