bt5_prototype: Udpate test for ObjectPropertyItem to check if the hash and objects are being created

It is useful to save some customizations, preferences, or eve additions for test business templates
This feature is managed by a new class: ObjectPropertyTemplateItem

bt5_prototype: Add export functions for PathTempalteItem and BusinessPackage as well as make createInstallationData more efficient

Problem:
This is a workaround for components being unable to get registered during
the tests.

Explanation:
After adding document component object, _p_oid is generated at the
last step of commit hook. This leads to problem that _registry_dict for
dynamic_class 'erp5.component.document' isn't getting updated with
the _p_oid of the component created.
This leads to failing of test because to validate object with same
reference, the checkConsistency function checks in the _registry_dict
for reference and _p_oid.

Solution:
Explicilty calling transaction.savepoint here generates the oid before validation, hence
make it available for the registry_dict in time.

But, this clearly is a workaround which is clearly not solving the real
problem of why the _p_oid isn't being generated at the right step.