Modularise db.py

[lim-james]

Description

These are the functions declared within db.py.

// user
def search_for_user(course_name, email):
def update_user_info(field_to_change, new_info):
// project
def update_project_info(project_name, field_to_change, new_info):
def insert_new_project(project_name):
def delete_project(project_name):

They should be declared in separate files - user & project.