Feature: transfers between members of different organisations

[franpb14]

I will make the current "time transfer for this offer" button work even if it is an offer from another organisation. This will allow different organisations to exchange time with each other.

The button will work as follows when the exchange is between different organisations:
member A and his organisation give one hour and member B and his organisation get one hour. So now the sum of time of the members of organisation A will be -1 and of organisation B will be 1.

For this Issue the way to share an offer from another organisation will be via URL, then we will look at how to implement a search engine.

[sseerrggii]

I think is a good first step. Someday we can show only accountability between organizations, limits of credit between organitzacions or other rules for interbank exchanges