767 icon radius changes

 Icon radius now scales with text height

Minor adjustment to positioning algorithm of `Util.Text.writeLineHorizontally`.

QE: Positioning for writing lines has been minorly adjusted.  Watch for changes in classes that use this functionality

Close #767.
You should use `assert.operator` so the message generated on failure is clearer. In addition, try to include a message that explains the error in more detail. ex:
```
assert.operator(circleHeight, "<", textHeight, "circle is not taller than the text");
```