Fix crashes due to logging problems
Unify the default widget settings.

Users can now set global defaults for widgets via:

from libqtile.widget.base import _Widget
_Widget.global_defaults = dict(
    font = 'Consolas',
    fontsize = 18,
    padding = 3,
)

in their config, before any widgets are created.

Conflicts:

	libqtile/widget/battery.py
	libqtile/widget/graph.py
	libqtile/widget/systray.py
Remove the need for ugly import hack in config

Now to configure global defaults for widgets, you can just do:

widget_defaults = dict(
    font = 'Consolas',
    fontsize = 18,
    padding = 3,
)

in your config.py

Conflicts:

	libqtile/confreader.py
	libqtile/widget/graph.py
Defaults refactoring for layouts
Update new widgets for defaults system
wip
Fix Zoomy config change.
Set background default value to None.
Remove redundant background default from graph.py.