* update-copyright: Silently skip nonexistent files.  Display filename on
update.  Don't update non-Red Hat copyrights.
* update-copyright (update_maybe): Accommodate perl-style copyright comments.
Throughout, change __attribute__ ((regparm (N))) to just __regN.  Throughout,
(mainly in fhandler*) start fixing gcc 4.7.2 mismatch between regparm
definitions and declarations.
* gendef: Define some functions to take @ declaration to accommodate _regN
defines which use __stdcall.
* gentls_offsets: Define __regN macros as empty.
* autoload.cc (wsock_init): Remove unneeded regparm attribute.
* winsup.h (__reg1): Define.
(__reg2): Define.
(__reg3): Define.
* advapi32.cc (DuplicateTokenEx): Coerce some initializers to avoid warnings
from gcc 4.7.2.
* exceptions.cc (status_info): Declare struct to use NTSTATUS.
(cygwin_exception::dump_exception): Coerce e->ExceptionCode to NTSTATUS.
* fhandler_clipboard.cc (cygnativeformat): Redefine as UINT to avoid gcc 4.7.2
warnings.
(fhandler_dev_clipboard::read): Ditto.
Throughout, update copyrights to reflect dates which correspond to main-branch
checkins.  Regularize copyright format.
* malloc_wrapper.cc (malloc_init): Re-add inadvertently dropped comment which
explains what's going on with the use_internal calculation.