Persist networking keystore

[GregTheGreek]

Includes

• Persists the networking keystore to disk
• Generates a new keystore if one doesn't exists
• Moves utils to its own package under node rather than a module within node
• Refactors the utils functions to support Vec<u8> rather than String

Issues

Closes #5

[kavanmevada]

[root@archlinux Desktop]# docker run forest
 2021-06-15T04:18:59.893Z INFO  forest::daemon > Starting Forest daemon
 2021-06-15T04:18:59.893Z INFO  forest_libp2p::service > Networking keystore not found!
keystore passphrase:  2021-06-15T04:18:59.894Z INFO  utils                  > Permissions set to 0600 on File { fd: 6, path: "/root/.forest/libp2p/keypair", read: false, write: true }
thread 'main' panicked at 'Error reading passphrase: Os { code: 25, kind: Other, message: "Inappropriate ioctl for device" }', forest/src/daemon.rs:80:46
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

I'm trying to run forest in docker got this error.

let passphrase = read_password().expect("Error reading passphrase");
Seems like it trying to read password from tty, shouldn't it read using rust std in/out io ?

reading from TTY requires some libc functions like ioctl and it's only unix specific only.