Fix Dash copyright violations!
Replacing any copyright headers that were formerly Dash with Crown is a violation of copyright and a liability to Crown project.
See here for an example of how MIT licensing requires it to be done: https://github.com/PIVX-Project/PIVX/blob/master/COPYING. Now take a look at the same Crown file: https://github.com/Crowndev/crowncoin/blob/master/COPYING
Dash copyright must be present. Fix the COPYING file and all the sources merged from Dash.