@Override
    public boolean equals(Object obj) {
        if (!(obj instanceof RoutingSpec)) {
            return false;
        }
        RoutingSpec rhs = (RoutingSpec)obj;
        if (!tables.equals(rhs.tables)) {
            return false;
        }
        return true;
    }
Convert a string value to a quoted value suitable for use in a config string.
<p>
Adds double quotes before and after, and adds backslash-escapes to any double quotes that was contained in the
string.  A null pointer will produce the special unquoted string null that the config library will convert back
to a null pointer.

@param input the String to be escaped
@return an escaped String
messagebus/src/main/java/com/yahoo/messagebus/routing/RoutingSpec.java