Remove rst note directive because not supported by GH.
Add batinfo as new optional dependency.
Add FreeBSD installation instructions.

Add support to the new net_io_counters() API.
Of course, still preserved backward compatibility with the now deprecated
network_io_counters().

Add batteries information (batteries % capacity is display in the footer/middle)

SimpleXMLRPCServer uses AF_INET as default address family.
This means it can only bind to IPv4 addresses.

GlancesXMLRPCServer is a wrapper class that makes it able to
listen on IPv6 connections.
The AF_INET or AF_INET6 address family ìs now determined by
socket.getaddrinfo() automatically.
This way the code is independent from the stack IP version.

Two small patches.

sed -i "s/49/ord('1')/g" glances.py
sed -i "s/97/ord('a')/g" glances.py
sed -i "s/98/ord('b')/g" glances.py
sed -i "s/99/ord('c')/g" glances.py
sed -i "s/100/ord('d')/g" glances.py
sed -i "s/102/ord('f')/g" glances.py
sed -i "s/104/ord('h')/g" glances.py
sed -i "s/105/ord('i')/g" glances.py
sed -i "s/108/ord('l')/g" glances.py
sed -i "s/109/ord('m')/g" glances.py
sed -i "s/110/ord('n')/g" glances.py
sed -i "s/112/ord('p')/g" glances.py
sed -i "s/115/ord('s')/g" glances.py
sed -i "s/116/ord('t')/g" glances.py
sed -i "s/117/ord('u')/g" glances.py
sed -i "s/119/ord('w')/g" glances.py
sed -i "s/120/ord('x')/g" glances.py
sed -i "s/121/ord('y')/g" glances.py

Moved last_update_times outside main() for unit tests

This reverts commit 74a9c935.