Add ability to recreate index before starting reindex

It is common case that Elasticsearch mapping has a breaking change, and we have to drop existing index and create it again and then start reindex.

All these 3 actions has to be done manually by an administrator, it is better to encapsulate it inside mod-search.

Introduce recreateIndex boolean property for /search/index/inventory/reindex API, and it should behave as following.

1. Given recreateIndex is true
   1. Than do the following before starting reindex operation:
      1. Drop existing index
      2. Create index with the latest mappings
   2. Start reindex operation.
2. Given recreateIndex is false or unspecified
   1. Than just start reindex operation (as it is currently)