v0.8.4

Fix (#73, #74) for all Exchange Adapters to mandate using a '.' (full stop) as the decimal point separator for formatting BigDecimal values.

Many locales default to a '.' and you might not be affected by this bug. Other locales, e.g. Czech Republic, default to a ',' (comma).

Exchanges always require a '.'

Thanks to @kuceraf for fixing this.