Pr issue 6

[peertrade]

This implements the requests in issue #6 for the /trades api, namely:

1. include payment method in the response
2. include volume field to indicate precise amount of primary currency traded.

note that volume could be calculated previously by multiplying price*amount, but the floating point multiplication often leaves numbers like 1.999999999 instead of 2.

note also that primary currency does not mean basecurrency aka bitcoin. Rather, primary currency is always the currency that is 2nd in the market identifer, eg xmr_btc, btc is primary. or btc_usd, usd is primary. The rule in bisq is that fiat currencies are always primary against basecurrency (btc), and basecurrency is primary against other cryptocurrencies. So if one wants to know amount of btc traded for any given market, one would use this logic:

    list($left, $right) = explode('_', $market_id);
    $btc_amount = $right == 'BTC' ? $volume : $amount;

I needed to link to PaymentMethod.java in the apidoc, and it was escaping all html entities, so I added a capability to detect markdown-style links in an API description or notes.

Sample Response ( from the updated apidoc )

[
    {
        "direction": "SELL",
        "price": "2375.72500000",
        "amount": "0.05000000",
        "volume": "118.78620000",
        "payment_method": "SEPA",
        "trade_id": "BLBJHGL-b644851d-f822-418a-8035-955f7a02eff9-051",
        "trade_date": 1501095828824
    },
    ...
]

[ManfredKarrer]

utACK