Pymyob

Fix Python3.4 support. (trailing comma after `**kwargs`..)

Fix Manager reprs.

13 Add support for primitive data types (date, datetime). This allows passing python datetimes directly into filter functions (no stringifying). For example:

invoices = myob.invoices.all(company_id=<company_id>, InvoiceType='Item', Date__lt=datetime(1992, 11, 14), orderby='Number desc')

12 Add Supplier endpoints.

11 Add Purchase/Bill endpoints.

9 Make use of trailing slashes consistent across all endpoints. Add endpoint tests.
10 Add support for `__gt` and `__lt`. Add request_kwargs filter building tests.