imporvements
- Add/imporve  __repr_ in Simulnet, Agent, Network, Localization, CLA
  and Constraints
Merge branch 'master' of github.com:pylayers/pylayers
Merge pull request #187 from niamiot/master

__repr__ for Simulnet suite
correction of typos
Merge branch 'master' of https://github.com/pylayers/pylayers
Merge branch 'master' of https://github.com/buguen/pylayers

Conflicts:
	pylayers/signal/bsignal.py