Added a newline between each pair of substrings in compare.character

This makes it easier to read for longer strings. 

Before:

```
x[1]: "<table><tr><tdcolspan='2'class='tooltip-title'>"+d.point_name+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric
y[1]: "<table><tr><tdcolspan='2'class='tooltip-title'>"+d.point_name+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric
x[1]: -name'>x</td><tdclass='tooltip-metric-value'>"+d.x+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric-name'>Thisi
y[1]: -name'>x</td><tdclass='tooltip-metric-value'>"+d.x+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric-name'>Thisi
x[1]: stheyaxis</td><tdclass='tooltip-metric-value'>"+d3.format('.2f')(d.y)+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip
y[1]: stheyaxis</td><tdclass='tooltip-metric-value'>"+d3.format('.2f')(d.y)+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip
x[1]: -metric-name'>Mygroups</td><tdclass='tooltip-metric-value'>"+d.color_group+"</td></tr><trclass='tooltip-metric'><tdclass='to
y[1]: -metric-name'>extra1</td><tdclass='tooltip-metric-value'>"+d3.format('.2f')(d['extra1'])+"</td></tr><trclass='tooltip-metric
x[1]: oltip-metric-name'>extra1</td><tdclass='tooltip-metric-value'>"+d['extra1']+"</td></tr><trclass='tooltip-metric'><tdclass...
y[1]: '><tdclass='tooltip-metric-name'>extra2</td><tdclass='tooltip-metric-value'>"+d['extra2']+"</td></tr><trclass='tooltip-me...

```

After:

```
x[1]: "<table><tr><tdcolspan='2'class='tooltip-title'>"+d.point_name+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric
y[1]: "<table><tr><tdcolspan='2'class='tooltip-title'>"+d.point_name+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric

x[1]: -name'>x</td><tdclass='tooltip-metric-value'>"+d.x+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric-name'>Thisi
y[1]: -name'>x</td><tdclass='tooltip-metric-value'>"+d.x+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip-metric-name'>Thisi

x[1]: stheyaxis</td><tdclass='tooltip-metric-value'>"+d3.format('.2f')(d.y)+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip
y[1]: stheyaxis</td><tdclass='tooltip-metric-value'>"+d3.format('.2f')(d.y)+"</td></tr><trclass='tooltip-metric'><tdclass='tooltip

x[1]: -metric-name'>Mygroups</td><tdclass='tooltip-metric-value'>"+d.color_group+"</td></tr><trclass='tooltip-metric'><tdclass='to
y[1]: -metric-name'>extra1</td><tdclass='tooltip-metric-value'>"+d3.format('.2f')(d['extra1'])+"</td></tr><trclass='tooltip-metric

x[1]: oltip-metric-name'>extra1</td><tdclass='tooltip-metric-value'>"+d['extra1']+"</td></tr><trclass='tooltip-metric'><tdclass...
y[1]: '><tdclass='tooltip-metric-name'>extra2</td><tdclass='tooltip-metric-value'>"+d['extra2']+"</td></tr><trclass='tooltip-me...

```