Bug 101086: Implement text alignment for shape-inside

This test checks that different values of the text-align property work correctly for shape-inside.

Below you should see 2 green squares in a line 4 squares wide, with different values of text-align. This tests that single-segment polygons work correctly.

You should see the same results when using block elements.

Below you should see 2 green squares in 2 lines 4 squares wide, separated by a 2 square space. The lines have different values of text-align. This tests that multi-segment polygons work correctly.

You should see the same results when using block elements.