Add Cars' Yearly Statistics

[apoltieva]

As a user, I want to see how much I spend on my car yearly. Steps:

• convert add tabs (https://github.com/resivalex/rails-bootstrap-tabs) in the view for /statistics endpoint, so that monthly and yearly statistics will be in different tabs
• create an appropriate queries in StatisticsController
• display user's yearly statistics on expences Note - see issue #40