add ancestry gem
migrate schema to add ancestry to comments
add has_ancestry to comment model
add nested comments generation in posts factory
add comments#new test
add comments#new action
add child comment form partial
implement comments#new view
add reply button to comment partial
add parent_id to permitted parameters in comments controller
add reply button to comment partial
add nested_comments method to comments helper
add nested comments to comment partial
add nested comments to posts#show view
add css class for nested comments
Merge branch 'feature/nested_comments' into develop
set version to 0.3.0
Merge branch 'release/0.3.0' into develop