add tset in Gis
add invfreqz
erge branch 'master' of https://github.com/pylayers/pylayers

Conflicts:
	pylayers/antprop/channel.py
bug fix in Signature.propath (bug if no airwall in the structure)
- bug fix in plotd Ctilde and Tchannel (polar 2nd axis is now in degree)
- rewrite doadod for Ctilde and Tchannel (call plotd)
improvement in polar function for polar diagram in D2.4
Merge branch 'master' of https://github.com/pylayers/pylayers

Conflicts:
	pylayers/antprop/channel.py
change default seek of signature algorithm in run4
Merge branch 'master' of github.com:pylayers/pylayers
- Modify ntheta/nphi to Nt/Np (from Fpatt)
- bug fix default Gauss pattern
- bug fix in polar
- bug fix in locbas (self.tang => self.tangl)
- improvement in plotd
- add plotad to vizualize Phi vs delays
- eval now pass a tangl and rangl to ctilde
- add a backtrace argument to run4 to allow visiting nodes already
  visited(experimental)
minor bug fix
Merge pull request #198 from niamiot/master

Bug fix in antenna rotations + new Tchannel visualizations.
removing trailing tabs in code
Merge branch 'master' of https://github.com/pylayers/pylayers
adding 'legend==True' option in Antenna.polar
Improve _repr__ in antenna.py
repairing antenna.pol3d function