Collective-searchandreplace

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- Allowed replacing with an empty string. Fixes 13. [maurits]

- Fix ensure we get the attributes of the base object in _getRawText.
[Gagaro]

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- In SearchAndReplace.pot added the ability to translate configure.zcml , searchreplacetable.pt.
Added Russian translation.

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- Added Russian translations. [serge73]

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- Added a behavior to add ISearchReplaceable on Dexterity content types.
Also added a profile to set this behavior on some content types.
[Gagaro]

- Only search and replace contents with the ISearchReplaceable interface.
[Gagaro]

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- Required ``plone.app.textfield`` in ``setup.py``.
[maurits]

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- Compatibility with Plone 5 and Dexterity content types.
[Gagaro]