Heroku free database row limit warning

[Ayush6602]

Heroku has sent a warning as we are very close to the max row limit allowed for the free postgresql server. Changing some models reference relations will help bring the amount of rows down as heroku limits number of row not columns.

[Ayush6602]

Will be shifting from heroku postgres to elephant sql as it does not have the row limit, also removing the postgres add on will allow to add heroku redis or memcached for better pereformance.