Use HAML instead of ERB

Signed-off-by: Joan Tiffany Siy <joan@teamcodeflux.com>
Create root page under home#index

Temporary home page.

Signed-off-by: Joan Tiffany Siy <joan@teamcodeflux.com>
Configure devise and simple roles

- generate installation files for devise
- generate User model
- configure user roles

Signed-off-by: Joan Tiffany Siy <joan@teamcodeflux.com>