Add functions to generate NER output result table

[haohangyan]

The output result table contains columns ['text', 'obj', 'obj_synonyms', 'don_article', 'groundings' , 'match']
There are three types of output:

1. Reference('obj', 'obj_synonyms') is None but goundings has values
2. Grounding is None but reference('obj', 'obj_synonyms') has values
3. Both grounding and reference have values
   The 'match' column specifies if there is a match between references and groundings