Fix export customers attributes.
Add delta sync for transactions and customers.
Merge branch 'master' of https://172.16.25.30/stash/scm/cem/plugin-magento

Conflicts:
	app/code/local/Boxalino/Exporter/Model/Mysql4/Indexer.php
Merge branch 'master' of https://172.16.25.30/stash/scm/cem/plugin-magento

Conflicts:
	app/code/local/Boxalino/Exporter/Model/Mysql4/Indexer.php
Merge resolve conflict
Merge branch 'master' of https://172.16.25.30/stash/scm/cem/plugin-magento

Conflicts:
	app/code/local/Boxalino/Exporter/Model/Mysql4/Indexer.php
Add delta export for products.
Small fix for memory leak.
Reduce sql query for customers
Memory usage optimization. Save attributes directly, without usage temporary table.