Fix wrapper issue

Fix wrapper issue, where given height is not sufficient for any line.

Fix clippath issue

v0.1.3

Fix clippath.

New endpoint

Expose clear cache for measurer.

Update d3

This version just updates d3.

First release

This version contains following items:

• Measurers efficiently measure the size of a piece of text when written to a particular SVG element, taking into account the CSS styles affecting that text.
• Wrappers calculate how best to fit text into a given space, based on results from the Measurer.
• Writers write text to a given SVG element based on specified options such as alignment, rotation, and animation.