Hover Popup for Host Groups

We've been using this internally for a while, really handy in our opinion. Seeing that 3.4.1 (we updated straight from 3.3.1) already added JavaScript stuff and the status.c has a lot of changes between versions, I'm now trying to push this patch upstream as it is a pain to manually edit status.c every update :-)

The patch is quite unintrusive in status.c; three printf's added, two printf's modified, one printf moved around a bit and one function has an extra parameter.
The JS-part I kept as simple as possible according to KISS-principles. This means it won't work on every browser. Works in our FF and Chrome. Feel free to go absolutely nuts with this part of the code.
The addition to cgiutils.h should be trivial to understand.

To apply the patch you will need Nagios Core 3.4.1. This is how I did it from the ground up:

gunzip nagios-3.4.1.tar.gz
tar -xvvf nagios-3.4.1.tar
cd nagios
patch -p0 < /where/the/patch/is/nagios-3.4.1-hover.patch
./configure --with-your --favorite=options, --your-mileage=may_vary
make all
make install

And it was running smoothly. Hope it makes your life easier like it did for us.