Fix window close, icon toggle logic

"Toggle" should mean "show or hide all windows", not "flip the visibility state
of windows". Case: one receiver window is open. When a new receiver is
connected, I also expect it to be open. Instead it is hidden, so I click the
icon. Now the new receiver window is shown, but the previous one is hidden.
Huh?! Indeed, let's fix that.
Fix window positioning of main windows

Previously, the intent was likely to position the receiver window near the
status icon. It did so by calling move followed by present. According to the
Gtk documentation, move() may fail if the window is hidden before.

Therefore present the window *after* determining the position, but *before*
moving it. (presenting the window before getting the position gives a Gtk
warning and has unpredictable behavior wrt. the window position).

As window positioning is now enabled, add additional logic to prevent overlap
of windows: position the first window near the status icon and others on the
left. This is not idea, e.g. when the status icon is on the left side of the
screen, but the idea of positioning windows near to each other is broken anyway.
next version will be 0.8.8
extended documentation of descriptors and registers
Merge remote-tracking branch 'origin/master'
fix str/unicode detection in Python 3.2
use 'with' lock syntax instead of acquire/release
minor clean-up in hidconsole
python 2/3: fix handling of first argument (unicode) of pack/unpack
handle all 07/0D register notifications
Merge pull request #40 from Lekensteyn/fixes

Fix window close, fix positioning of new windows
Merge remote-tracking branch 'origin/master'
fix hidconsole for python 2/3
simpler (and dumber) way to position receiver windows initially
updated debian/control dependencies