Attribution for various contributors.

Conflicts:
	THANKS
Handle errors from TAP-Win32/64 adapter in a better way.

Before, the tapreader thread would just exit immediately after encountering the
first error, without notifying the main thread. Now, the tapreader thead never
exits itself, but tells the main thread to stop when more than ten errors are
encountered in a row.
Attribution for Dennis Joachimsthaler.
Update copyright notices.
Fix compiling for Windows.
Check whether OpenSSL has support for GCM.
Releasing 1.1pre10.