- added new method returning TaxCalculations object so new data it's accesible: tax_amount and tax.
preparing decorators to execute different codes depending of the number type: integer or float
format the price with number_to_currency instead of number_with_precision.
- the format can be configured in locales and always gets a nice output
Merge branch 'develop'

* develop:
  format the price with number_to_currency instead of number_with_precision. - the format can be configured in locales and always gets a nice output
  preparing decorators to execute different codes depending of the number type: integer or float
  - added new method returning TaxCalculations object so new data it's accesible: tax_amount and tax.