Coupling:

+ Added a new coupling function for the Jansen and Rit model.
* Coupling desesperately needs to be reviewed.  
* The couplings Datatypes are currently unused.
* Currently there is almost one coupling per model. 
? Consider linking a model to a coupling function.
? Make the coupling aware of the models coupling variables and which operations should be performed. 



git-svn-id: https://repo.thevirtualbrain.org/svn/tvb/trunk/scientific_library@6344 1c0e02f0-7929-43c0-8fb3-3293bf43b0d1
Models:

+ Updated Jansen and Rit model. The long range coupling term was somewhat incorrect.
+ With the recently introduced SigmoidalJansenRit coupling function it should be safe to use this model.
+ See demos/region_stochastic_jansen.py


git-svn-id: https://repo.thevirtualbrain.org/svn/tvb/trunk/scientific_library@6345 1c0e02f0-7929-43c0-8fb3-3293bf43b0d1
region-stochastic_jansen.py:
----------------------------
+ Updated demo
   
   *The noise scaling has been corrected
   *It makes use of the right coupling function  



git-svn-id: https://repo.thevirtualbrain.org/svn/tvb/trunk/scientific_library@6346 1c0e02f0-7929-43c0-8fb3-3293bf43b0d1
Merge branch 'trunk' of https://github.com/the-virtual-brain/tvb-library into trunk