CRM-1187: Find the best batch sizes for magento import
 - updated magento soap transport
 - added page size to magento import iterators
 - set smaller import batch size
 - updated unit tests
Merge pull request #661 from laboro/ticket/CRM-1187_batch_size

CRM-1187: Find the best batch sizes for magento import
Merge remote-tracking branch 'remotes/dev/master'