Eve-elastic

++++++++++++++++++

- fix reindexing when task info is missing.

++++++++++++++++++

- refactor reindexing

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- add config `ELASTICSEARCH_FIX_QUERY` to control if we want to handle old queries
- add config `ELASTICSEARCH_FIX_MAPPING` to control if we want to handle old mapping

++++++++++++++++++

- change find return to be cursor, count
- fix overriding query inside match query

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- call filter_callback without req param on TypeError

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- pass req to filter callback