Get a list of your Opensolr Indexes

1. GET https://opensolr.com/solr_manager/api/get_index_list
2. Parameters:
   1. ​email - your opensolr registration email address
   2. api_key - your opensolr api_key

3. Example: https://opensolr.com/solr_manager/api/get_index_list?email=PLEASE_LOG_IN&
   api_key=PLEASE_LOG_IN