Flexibility in type specs

[cbusbey]

From the QFIX 201 presentation, @mgatny sez

 And the FIX message should have the following:
        | MsgType  | "NewOrderSingle" |
        | Symbol   | "AAPL"           |
        | Side     | "BUY"            |
        | OrderQty | 1.0              |
        | Price    | 10004.0          |
        | OrdType  | "LIMIT"          |

• It would be better if I didn't have to put ".0" on the end of my price and qty, since I don't actually want it to be formatted that way in the message itself. Could be an interaction between rspec and the type of the quickfix field (e.g. float/bigdecimal)? Maybe we could add a feature where you could quote it, like "10004" to force a string comparison.