Collaborative environment/marketplace M4

Summary
A first version of the collaborative space for the PPP will be provided in M4, to ensure that members start collaborating early enough. This will be possible because with BDVA is a beneficiary BDVe can capitalise on existing work. This will allow the rapid parametrization of tools to quick-start some activities. However, it is expected that this environment/marketplace will be much richer in terms of functionalities. Therefore a full version of it will be presented in M18.