Tag selector Headspin coding challenge

The front end module satisfies the following requirements:

Be able to delete a tag from a session.
Be able to add a tag to a session.
When a tag is added to a session, UI immediately updates the statistics for any selections that include the session based on the new tag.
When a tag is deleted from a session, UI immediately updates the statistics for any selections that included the session based on that tag.
When the mouse hovers a selection, its corresponding sessions get visually highlighted in some way.
Be able to delete a selection.
Be able to create a new selection. When the new selection is created, it immediately updates with statistics, if there are any objects that pass its filter.

Extras:

Selections as defined above take the form of a logical disjunction (a=x or b=y). Extend selections to be disjunctions of conjunctions: (a=x and b=y) or (a=z and c=p and d=m) or ...

1a. Duplicate tag names allowed in conjunctions (a=x and a=y) or (a=m and a=n)
```
This involves allowing tagging a session with multiple tags
that share a name.
```
Read-only tags. Some download sessions might be tagged with Read-only, or "system tags" that cannot be deleted or modified, but can still be selected for like a regular tag.

Available Scripts

In the project directory, you can run:

Runs the app in the development mode.
Open http://localhost:3000 to view it in the browser.

Builds the app for production to the build folder.
It correctly bundles React in production mode and optimizes the build for the best performance.

The build is minified and the filenames include the hashes.
Your app is ready to be deployed!

See the section about deployment for more information.