public static int hash(String key) {
        return hash(Utf8.toBytes(key), 0);
    }
Hashes a string, by calling hash(byte[] key,int initval) with
the utf-8 bytes of the string as key and 0 as initval.
Note: This is copying the string content, change implementation to
use efficiently on large strings.

bratseth
vespajlib/src/main/java/com/yahoo/collections/BobHash.java