fix: update notifications

Updating notifications to look closer to the design specifications.

• Changed the width of the notification
• Changed the background color and text color of the notification depending on error or info
• Use CSS classes instead of inline styling
• Mark the input that is incorrect

Does not add ability to close out notification (they timeout after 5 seconds).
Does not add ability to have multiple notifications on screen at one time

Related to gitlab#11474 (closed)

Before

After