Adds sort function to Tasks table headers.
Redirects task destroy button to all or incomplete list.
Adds sign up link and form.
Adds password column to user database.
Adds current user name to navbar.
Adds sign out link.
Adds bootstrap to navbar and user name.
Adds error messages for invalid user sign up credentials.
Makes sign up error messages red.
Adds user sign in page.
Adds password field to new user form.
Adds first and last name field to sign up page.
Adds formatting and headings to sign in and sign up pages.
Changes sign in button to button class.