Bug resolved in resource mapping to topics

**Bug resolved** 

 *  ```nroer_data_entry.py```  --> script modified for mapping resource to topics correctly according to hierarchy level.
      * Query modified for finding topics. also check is made to find its exact prior node and accordingly select topic node for making teaches relation to topics

* ```sync_existing_documents.py``` --> script modified for updating prior node fields of all nodes by checking nodes collection elements. , Also stripped name values of theme, theme items and topics nodes.

* ```set_teaches_relation.py```  --> Script added for mapping resources to exact topics according to topics hierarchy level.
    * Script deletes  existing  relation to incorrect topics and creates new relations by checking topics prior node context.

* ```themes_entry.py```  --> Script modified by stripping all incomming values of theme map csv by seting name field.