SDLNet_TCP_Close() not only closes, but also release the resources.
Therefore, we must not close the socket if another thread attempts to
read it.
For that purpose, move socket closing from server_stop() to
server_destroy().
Do not wait 100ms anymore to let the server print any exception: we
justly want to ignore them.
Moreover, there is no nanosleep() on Windows, so this solve another
problem.
The server is built as an APK to simplify the build, but in fact this is
a simple jar (it is not even signed).
In order to avoid confusion, rename it to .jar, so that users do not try
to "adb install" it.
Also rename it from "scrcpy" to "scrcpy-server" to distinguish from the
client-side.
The server path may be customized using SCRCPY_APK. If its basename is
different from "scrcpy.apk", it will be pushed with a different name,
so the execution would fail.
Therefore, force the push target filename.
Accept a parameter to limit the video size.
For instance, with "-m 960", the great side of the video will be scaled
down to 960 (if necessary), while the other side will be scaled down so
that the aspect ratio is preserved. Both dimensions must be a multiple
of 8, so black bands might be added, and the mouse positions must be
computed accordingly.
