Added related posts to each project page
Projects: Add associated_tag object.

This is mainly for posts to find a relevant
project based off a tag that the post has.

i.e. Post "Matrix Update 0 ", Tags: "matrix" would
link to the matrix project page.

Add a serialize property for the api.
API: Add method to get projects by a tag.

Retrieves JSON of all the projects associated with
a post tag.
Flake8 fixes.
DB: Add associated_tag_id migration.
Init: Add project models for Flask-Migrate to detect.
Users: Make subject fields not nullable.

This was done in order to make flask-migrate
detect the correct migration.
Merge branch 'associate-tags-with-projects' into link-project-tags-to-project-pages
Retrieve list of projects and update tag href is necessary
Made it possible to obtain the assocTag name on the indiv project pages
Merge pull request #126 from CalPolyIEEE/link-project-tags-to-project-pages

Link project tags to project pages

* Added related posts to each project page   1c7a678
* Projects: Add associated_tag object. …  82bbed5
* API: Add method to get projects by a tag. …   ac62bca
* Flake8 fixes.   fe1b0f9
* DB: Add associated_tag_id migration.    f8b44d2
* Init: Add project models for Flask-Migrate to detect.  757ede8
* Users: Make subject fields not nullable. …    e38aea1
* Merge branch 'associate-tags-with-projects' into link-project-tags-to… …  449fcd2
* Retrieve list of projects and update tag href is necessary edb8dd9
* Made it possible to obtain the assocTag name on the indiv project pages