make validation in poem model that checks that snap_count is not negative
fix poems_controller_spec for index
make poem attr snap_count  on client side wait for a success response on the server side before updating snap_count
Merge pull request #10 from anirudh-eka/styling

Styling
switch db to postgresql
Merge pull request #12 from anirudh-eka/switch_database_to_posgres

switch db to postgresql
make poem title validation max length to be 40 characters
make new poem title counter in poem_new.js
make snap button disappear with successful sign out
add a welcome message to user when poem_new.js initializes
make small styling changes