Monitor Task Completion and Record Task Completion

[ShanMehr]

Feature Overview:

Implemented monitoring of task completion for the following time periods:

1. year
2. month
3. week
4. all-time

   User Metrics Monitoring Description

   When a task is completed a new user metric entry if none has been previously added. Otherwise, the user metric is updated, and if the period of the current date no longer falls within the period of the user metrics the period is updated.

   Created user_metrics table

   The user metrics table keeps track of the user owner and contains nested objects for user metrics for each time period.

Testing (How to view feature)

0. Login/Register
1. Create a task
2. navigate to display tasks http://localhost:3000/display-tasks
3. Set one of the tasks as completed
4. Navigate to the mongodb user_metrics and verify that the user_metrics was incremented/altered

[ShanMehr]

Except for stated consistency comments, lgtm

Sounds good, I revised the formatting of the code to switch from camel case to snake case