Join the entire library into a single script package

This allows the code to be used without requiring Composer
or Packagist.
Merge pull request #36 from maetl/join-php-package

Join the entire library into a single script package
Update link to bigcommerce.php
Merge pull request #34 from saranyan/master

Added product/images method support
Rename getImage to getProductImage
Packaging 2.0.4
Fix issue with defaulting to the base resource when not otherwise specified
Fixing issue with PUT requests resetting the curl state
Default resource id to 0 if the resource is not an entity
Add isset check for resource properties
optionset options support for POST
optionset POST support