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Released at 2017-11-08 14:55 +0200.
* Add option for custom pdf config to posti carrier
* Change default pdfConfig for the PDF printout
* Change the default pdfConfig, so that the pdf would fill the
entire page. Set it to accept custom pdfConfig values from
plugin's implementations in different projects.
* Make sure decimal data can be sent as JSON
* Require the simplejson library for requests to add Decimal
serialization support.