Hooks Up Community Creation Form to Server

[Step7750]

• Restructures Form Building
• Adds Async custom validator for checking if the name exists while typing
• Adds regex pattern validation to name
• Community creation now successfully creates a community in the server with a little snackbar that shows status
• Slightly simplifies the CSS (please don't hate me @xiningchen, it was having conflicts with the user resizing the text areas)
• Disables submit button during submission
• Changes title to "Create Community" rather than "Community Creation"
• Adds hint for required fields from a glance

Closes #43

TODO: Redirect to the newly created community when created

[bandgeekdante]

Can you merge this with a branch that connects the sidenav to the server?