Adapt platform to new soledad server entrypoints
Soledad server now has 2 distinct entrypoints:
- a publicly accessible api for users synchronization. TLS is currently handled by soledad server, but we want to move it to nginx so soledad doesn't need to care about this.
- a locally accessible api for mail delivery. This should be accessible by the MX node, so it needs an stunnel config when MX and soledad server run in distinct nodes.
In order to support that, the platform has to: