Added functionality to count tweet dates

Created Tweets Controller.  Controller has route to get dates of tweets, which currently calls one method to count the month/year combination of all tweets in a hash.  Todo: modify AJAX request to return these dates upon user login, then use highcharts to display visually.
Added highcharts/analytics template.

Modified index view to have functionality to hide/show divs for analytics and search function.  Removed placeholder div for facebook results.  Template highchart of time series animated. TODO: use calculated data in highchart.
Highchart with number of tweets added.

Highchart displays upon clicking Analytics button.  Currently shows number of tweets per month/year.  TODO: convert x-axis values to Datetime values for each month/year.
Minor changes to analytics and search

Changed toggles on buttons for analytics and search functions.  Now hides the other one.  Also changed a couple of variable names.  Skeleton and routes set up for Sentiment analysis chart.
Merge pull request #4 from amolborcar/implement_highcharts

Implement highcharts