Improve Bitstamp's exception handling
Merge pull request #719 from timmolter/bitstamp-exceptions

Improve Bitstamp's exception handling
Implement Coinsetter RESTful/JSON API: Ping.
Implement Coinsetter RESTful/JSON API: ClientSession.
Implement Coinsetter RESTful/JSON API: Customer Account.
Implement Coinsetter RESTful/JSON API: Financial Transaction.
Implement Coinsetter RESTful/JSON API: Order.
Implement Coinsetter RESTful/JSON API: Alerts.
Implement Coinsetter RESTful/JSON API: generic service wrapper.
Add javadoc.
Merge pull request #720 from sutra/feature/coinsetter

Implement Coinsetter RESTful/JSON API: ClientSession, Customer Account, Financial Transaction, Order, Alerts and Ping.
Allow Integers, BigIntegers etc., not just Longs.
Improve cancellation of open orders and requesting order history
Merge branch 'develop' into okcoin_cancel
Resolve #708;
normalize Ticker and LimitOrder builders: name methods after Effective Java Builder;
 TickerBuilder: rename to Builder, remove newInstance();
 LimitOrder.Builder: create object using the standard constructor
Add LimitOrder.Builder.from() to allw user build new order from existing ones.
In Coinsetter tests, uses UTF-8 to read resources.
Merge pull request #722 from rafalkrupinski/builder

normalize Ticker and LimitOrder builders
Merge pull request #723 from sutra/develop

In Coinsetter tests, uses UTF-8 to read resources.
Use exceptions with BitstampTradeService