Router: Prep for router encryption types (Proposal 156 WIP)

...le/java/src/net/i2p/router/web/helpers/NetDbRenderer.java

...er/java/src/net/i2p/data/router/RouterPrivateKeyFile.java

...et/i2p/router/networkdb/kademlia/FloodfillMonitorJob.java

.../java/src/net/i2p/router/startup/CreateRouterInfoJob.java

...er/java/src/net/i2p/router/startup/LoadRouterInfoJob.java