Strings vs Symbols in order methods

[cheerfulstoic]

This came up here:

http://stackoverflow.com/questions/31946711/neo4j-rb-cant-use-order-by/31947456#31947456

Basically, because of the Query class, in an order method a String is handled differently than a Symbol.

First thing is that this should be documented

Secondly, we could maybe be smarter about this. If the string matches something like /^[\w_]+$/ we can assume it's a property that they're specifying. Also maybe this rule should be from ActiveNode/QueryProxy and not in Query