Bug fix in antenna rotations + new Tchannel visualizations.

# Signature
+ change default seek of signature algorithm in run4	a88cc27
+ add a backtrace argument to run4 to allow visiting nodes already …	76fa06f

# Antenna & Ctilde
+ Modify ntheta/nphi to Nt/Np (from Fpatt) …	b20427b
+  bug fix in locbas (self.tang => self.tangl) …	b7e7c3d
+ eval now pass a tangl and rangl to ctilde	e75729f