Upgraded Django to 1.7.3
Upgraded Django to 1.7.3

CodeforLeipzig/luftqualitaet_sachsen,plumps/luftqualitaet_sachsen,plumps/luftqualitaet_sachsen,CodeforLeipzig/luftqualitaet_sachsen,CodeforLeipzig/luftqualitaet_sachsen,CodeforLeipzig/luftqualitaet_sachsen