update getBlog function to show blog post as teasers
added custom repository class to Blog
removed query for entities in the controller and added it to a custom repository class for the Blog class
create the Comment Entity Class and generate the Repository
update .gitignore - remove composer.lock from git
installed doctrine migration bundle and added it to AppKernel
add references to the blog entities and implement function to specify the loading order of fixtures - blog before comments
defined fixtures for Comment entity
added a Comment Repository , updated the Blog Controller to show comments , updated Templates and CSS