* move templating code under the core package
* make from_predefined part of the Pipeline API
* add tests
* amend release notes
* import under haystack package
* Apply suggestions from code review
Co-authored-by: David S. Batista <dsbatista@gmail.com>
* from_predefined -> from_template
* remove template inheritance for more readability
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Co-authored-by: David S. Batista <dsbatista@gmail.com>
