Move events stats in Statistics, add ticket distribution

app/views/admin/stats/_tickets_distribution.html

@@ -0,0 +1,79 @@
+<style>
+
+.arc path {
+  stroke: #fff;
+}
+
+</style>
+
+<script>
+
+var width = 250,
+    height = 250,
+    radius = Math.min(width, height) / 2;
+
+var color = d3.scale.ordinal()
+    .range(["#9ECAE1", "#6baed6", "#DEEBF7"]);
+
+var arc = d3.svg.arc()
+    .outerRadius(radius - 10)
+    .innerRadius(0);
+
+var pie = d3.layout.pie()
+    .sort(null)
+    .value(function(d) { return d.value; });
+
+// Where to put the chart
+var svg = d3.select("#tickets_distribution").append("svg")
+    .attr("width", width)
+    .attr("height", height)
+  .append("g")
+    .attr("transform", "translate(" + width / 2 + "," + height / 2 + ")");
+
+var data = <%=raw @tickets_distribution.to_json %>;
+
+var g = svg.selectAll(".arc")
+    .data(pie(data))
+  .enter().append("g")
+    .attr("class", "arc");
+
+g.append("path")
+    .attr("d", arc)
+    .style("fill", function(d) { return color(d.data.status); });
+
+// Put text inside every piece of the pie-chart
+g.append("text")
+    .attr("transform", function(d) { return "translate(" + arc.centroid(d) + ")"; })
+    .attr("dy", ".35em")
+    .style("text-anchor", "middle")
+    .text(function(d) { return d.data.percent +"%"; });
+
+// Title of chart
+svg.append("text")
+    .attr("class", "title")
+    .attr("x", radius)
+    .attr("y", -radius+10)
+    .text("% of pre-registered");
+
+// Create & position legend
+var legend = d3.select("#tickets_distribution").append("svg")
+    .attr("class", "legend")
+    .attr("width", radius * 2)
+    .attr("height", radius)
+  .selectAll("g")
+    .data(color.domain().slice().reverse())
+  .enter().append("g")
+    .attr("transform", function(d, i) { return "translate(0," + i * 20 + ")"; });
+
+legend.append("rect")
+    .attr("width", 18)
+    .attr("height", 18)
+    .style("fill", color);
+
+legend.append("text")
+    .attr("x", 24)
+    .attr("y", 9)
+    .attr("dy", ".15em")
+    .text(function(d) { return d + " (" + data.filter(function(v){return v.status === d;})[0].value + " or " + data.filter(function(v){return v.status === d;})[0].percent + "%)" ; });
+
+</script>