add csv require to application controller
add respond to block to about action in static_pages controller for csv export
add button to about page to export stats to csv
update helper methods for stats to provide formatted/unformatted choice
update about page calls to stats methods to use new format parameter
build view to respond to csv export for about stats
Merge pull request #39 from cmckee-dev/ryan/csv_export_stats

Implement CSV export for application stats
Merge branch 'master' of https://github.com/cmckee-dev/DPL-Capstone