fedorahosted used to be our home, but we are now hosted at sourceware.

Change the elfutils project home to http://elfutils.org/
Point hosted services (email, release, git, bug tracker and web pages)
to https://sourceware.org/elfutils/

Move design notes from README to NOTES.
Add URLs for home, releases, bugs, git and mailinglist to README.

Make the --version output of all tools the same by using a common
print_version function and update the publicly shown copyright holder
to the elfutils developers.

Signed-off-by: Mark Wielaard <mark@klomp.org>