Avoiding fallback to id attribute if there is a id field defined
feature #307 Avoiding fallback to id attribute if there is a id field defined (peterrehm)

This PR was squashed before being merged into the 3.0.x-dev branch (closes #307).

Discussion
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Avoiding fallback to id attribute if there is a id field defined

This PR fixes #276 to avoid the default fallback to the id attribute even if there has been
an field with the id name specified.

Commits
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bf0a4f1 Avoiding fallback to id attribute if there is a id field defined