improve charts: refactor SiteCount to take an iterator and an aggregating key as arguments.
improve charts: reuse SiteCount on StateBar chart, add Construction/Permit to bar chart.
improve charts: reuse SiteCount on StateBar chart, add Construction/Permit to bar chart.
improve charts: same refactor for country bar code, extract color constants.
improve charts: same refactor for country bar code, extract color constants.
improve charts: margin between charts
improve charts: use consistent legend properties
improve charts: charts lib upgrade
improve charts
Merge branch 'feature_improved_charts'