shorter variable name
bugfix: from __future__ import division must occur first
create subsystems using functions in conitnuous_pwa example

because it emphasizes the problem's structure
abbreviate matplotlib to mpl
move polytope.plot inside polytope

for object-oriented plotting and to avoid cyclic imports
rm polytope.plot
underscore get_patch -> _get_patch in polytope.polytope
logging in polytope
return from Polytope.plot and polytope._get_patch if no mpl, logging warning
rm redundant import in hybrid
improve LtiSysDyn docstring
minor style, use 'and' instead of '&' python operator
new method: LtiSysDyn.plot
new methods: Polytope.bounding_box, Region.bounding_box
improve bounding_box docstring
style
rename variables in polytope.is_inside
new methods: Polytope.__contains__, Region.__contains__
allow tuple as point argument to  is_inside
integrate is_inside into Polytope.__contains__ and Region.__contains__