v1.6

New release with added functions and improved error handling:

• new functions: similarProductSearch(), creditsRemaining()
• added size parameters in barcodeImage()
• retry API calls on 429 response

v1.5

New release with added methods:

• categorySearch() - search for keywords within a product category
• issuingCountryLookup() - find the issuing country of a barcode
• isbnLookup() - lookup books by ISBN-10 or ISBN-13

v1.4

Bugfix release

v1.3

Set HTTP timeout, better error handling, automatically URL encode search strings

v1.2

Added barcodeSearch() function with mode detailed result and improved the documentation.

v1.1

updated license information

v1.0

first release