Now supports connecting to input ports and you can control the number of
columns of meters with -c, -c 1 will give you a vertical strip.
Input monitoring "works" by disconnecting everything from the port,
connecting it to the meter in and connecting the monitor out of the meter
to the original port. When it quits it tries to put things back the way
they should be, but it might not always get it right.
If you run too many (8+) then things start to get dodgy, jack carries on
running, but you can't quit meters. I don't know why.
Thanks to Joern and Gerd for testing the extra-alpha versions, and Kai for
fixing the autoconf mess.