Add hooks in ObjectTemplateItem in to allow code execution at defined points in installation procedure to limit code duplication.
Merge CategoryTemplateItem's install method with ObjectTemplateItem's.
Implement a way to save and restore UIDs of replaced documents. This solves a problem of "uid changed" errors when an existing document is being replaced by installed one.


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@22282 20353a03-c40f-0410-a6d1-a30d3c3de9de