Update Copyright header point to COPYING file
Point to a file containing the license rather than including
it in every single source file. This will make it easier to
manage the license in the future without another humongous
commit.
https://fedorahosted.org/ipsilon/ticket/126
Signed-off-by: Rob Crittenden <rcritten@redhat.com>
Reviewed-by: Patrick Uiterwijk <puiterwijk@redhat.com>