Set refresh to 10 sec.

According to the [API](https://en.bitcoin.it/wiki/MtGox/API/HTTP)
docs for MtGox:

    All API methods are cached for 10 seconds.  Do not request results more
    often than that, you might be blocked by the anti-DDoS filters.
Add str() to conditional

Was comparing an integer to a string, causing an invalid
classification for order status.
Simulation default

Make simulation mode default
Transcaction fee

Add standard MtGox transaction buy fee (0.55%/0.6%) to simulation.