add seed data to help test database
bugfix/change @locations to @locationpins

 - To help display all the posts.
 - Needed to further dereference given the creation of the join/through location pin table
Merge pull request #79 from Lrmanfre/helper/seed-data

add seed data to help test database
Merge pull request #80 from Lrmanfre/bugfix/migration-change-to-locations-and-lpins

Bugfix/migration change to locations and lpins