define postgreSQL schema and document in wiki

[ortonomy]

Need to define the core data storage for the backend.

Acceptance:

• define tables
• define columns
• documented in wiki article: DB schema

[ortonomy]

From Wiki:

Table: Users
[has many: Reviews, Comments, ??Projects]

id: uuid
name: text
email: text
password: text
admin: bool

Table: Freelancers
[has one: User, has many: Roles, Projects, Reviews, Comments]

id: uuid
firstname: text
lastname: text
fulltime: bool
email: text
phone: int
date_joined: timestamp
date_updated: timestamp
current_role: uuid
active: bool
hours: int
rate: int
availability: ???
timezone: char[3]
deadlines_hit: int
deadlines_missed: int

Table: Projects
[has many: Freelancers, Reviews, Comments, Users]

id: uuid
date_opened: timestamp
date_completed: timestamp
active: bool
description: text
on_time: bool (Handling/tracking of deadlines, esp. within an ongoing project, is complicated and needs more thought.)

Table: Reviews
[has one: Project, has many: Freelancers, Reviews, Comments]

id: uuid
date_submitted: timestamp
date_updated: timestamp
stars: int
review: text

Table: Comments

id: uuid
date_submitted: timestamp
date_updated: timestamp
author_id: uuid
title: text
body: text

Table: Roles

id: uuid
title: text
rate: int
date_started: timestamp
date_ended: timestamp

[ortonomy]

This still depends on #12 , #11 , #10