for objects, first try almost-equal then equal if no  __sub__ operator is defined
addition of intervals now ok
import Goulib.tests instead of nose
pairwise(iterable,loop)
tests updated to avoid conflicts between pythoscope and Goulib.tests
+ TODO:s removed for unimplemented tests
"the right way to implement stuff" : angle
Vector2.angle rewritten to use math2.angle
tests added
added some "right ways to calculate stuff"
cleaned
Group.from_dxf added
added option to runmodule to bypass redirection
new
Drawing blocks
solved keys problems in GeoGraph.copy when no rtree acceleration
1.7.3 : Python 3.x compatible
travis tests on python 3.4