netfilter: add my copyright statements

Add copyright statements to all netfilter files which have had significant
changes done by myself in the past.

Some notes:

- nf_conntrack_ecache.c was incorrectly attributed to Rusty and Netfilter
  Core Team when it got split out of nf_conntrack_core.c. The copyrights
  even state a date which lies six years before it was written. It was
  written in 2005 by Harald and myself.

- net/ipv{4,6}/netfilter.c, net/netfitler/nf_queue.c were missing copyright
  statements. I've added the copyright statement from net/netfilter/core.c,
  where this code originated

- for nf_conntrack_proto_tcp.c I've also added Jozsef, since I didn't want
  it to give the wrong impression

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_conntrack_tftp.c b/net/netfilter/nf_conntrack_tftp.c
index e9936c8..e68ab4f 100644
--- a/net/netfilter/nf_conntrack_tftp.c
+++ b/net/netfilter/nf_conntrack_tftp.c
@@ -1,5 +1,5 @@
 /* (C) 2001-2002 Magnus Boden <mb@ozaba.mine.nu>
- *
+ * (C) 2006-2012 Patrick McHardy <kaber@trash.net>
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.