Create a simple zone manager for scion lab users

[fehlmach]

A user must be able to manage its domain (zone). He should be able to do it through a web interface with input validation. He should be able to perform the following changes:

• Adding/Updating/Removing Assertions from the zone file. (not yet implemented)
• creating/updating/removing key pairs (use internally keyManager)
• updating (all or parts of) rainsd config (not yet implemented)
• updating (all or parts of) publisher config (not yet implemented)
• change addr of rainsd server

It may support:

• decide on the publishing interval (how frequently zonePub is called). Otherwise the publishing interval would be determined by the signature lifetime configured in the zonepub config.