This removes the isCore flag and allows us to dynamically calculate the
core flag for contributors.
For now this is just us (the first 6 contirbutors)
Also we do not need the default contributor anymore because the deploy
user has the role to manage contributors and can create the first real
contributors.
This reuses the kredits library functions in the helper scripts and
seeds. We no longer need to add IPFS hashes manually but simply can
provider contributor/proposal data.
This makes it easier to handle truffle arguments which we for example
need to specify the network.
So we ask the user for input instead on using the argv array which might
change.
So far we only allowed calls to the Contributors contract from the
Operator. With the new registry concept we can call functions again
directly on the Contributors contract (without the need to call it through
the operator).
This changes the authentication for the contributor management functions
to allow either core contributors or the operator to call them.
In the future I envision a bit more flexible and configurable
authentication concept that can more easily evolve over time.
