Added Grid component and cleaned up login modal.

[JoshuaSand0val]

Grid has two props:

• Width (Controls the width of the Grid container itself. By default it takes the max width it can.)
  • Values: xs, sm, md, lg, xl, xxl
• Align (Aligns the contents of Grid container)
  • Values: start, end

[Varuna3]

merged with #165