Provide the stock information for the given dates & stock

1. Clone the repo and cd quandl-stock-api
2. bundle - to install the require gems
3. mailcatcher - to check the mails in locally
4. Get the api from the quandl api doc eg: 8tREfmA_XXXXXXXXXX
5. rspec is for unit test coverage
6. rubycritic will you the code quality report - mine (93.41/100)
7. Incorporate the rubocop for the code analyzer and formatter

API_KEY=XXXX ruby stock.rb AAPL Jan 1 2018 - Jan 5 2018

02.01.18: Closed at 172.26 (169.26 ~ 172.3)

03.01.18: Closed at 172.23 (171.96 ~ 174.55)

04.01.18: Closed at 173.03 (172.08 ~ 173.47)

05.01.18: Closed at 175.0 (173.05 ~ 175.37)

First 3 Drawdowns:

-1.8% (172.3 on 02.01.18 -> 169.26 on 02.01.18)

-1.5% (174.55 on 03.01.18 -> 171.96 on 03.01.18)

-1.3% (175.37 on 05.01.18 -> 173.05 on 05.01.18)

Maximum drawdown: -1.8% (172.3 on 02.01.18 -> 169.26 on 02.01.18)

Return: 2.740000000000009 [+1.6%] (172.26 on 02.01.18 -> 175.0 on 05.01.18)