Metrics calculation server infrastructure

We need to set up a private server which can make metrics calculations on clients' servers, send the metrics and hashes back to clients and securely erase passwords.

Tasks:
- set up a specialised Symfony app which can authenticate users against the www/upload app's database
- [can-delay] deploy a confined Apache (talk to Petr Marchenko to deploy Wedge on study.cs)
- decide on an API to send information between client and server
- build server certificate and embed it into client
- implement client password sending and metrics receiving code
- implement server password receiving and metrics sending code
- implement metrics calculations on server
- [can-delay] audit API and server