Revert "Remove admin"

This reverts commit b3607e3b6bd05717dbb940d7aa15eda96ae355ff.
Add font awesome and bootstrap gems
Add basic layout for the whole application
Add basic main index page
Add users index page
Add user profile page
Remove currency index page
Add pricepoint index page
Minor fixes
Add ability to create pricepoints and currencies
Add flash error message to layout
Add discount index page
Remove show item path for physical and digital item
Add digital item index page
Add physical item index page
Add bundle index page
Ad store item index link, remove shopping section
Add store item index page
Add promotion index page
Simplify admin default layout