Non-integer point font size

Font size can be set to a non-integer value.

You can now set a point font size with a non-integer value, for instance 8.3pt:

<Style name=".big">
  <StyleAttribute name="fontSize" value="18.5pt">
</Style>
<Style name=".small">
  <StyleAttribute name="fontSize" value="8.3pt">
</Style>

This fixes a small issue: the default font size on Windows™ is 8.25, but as GDC only managed integer font size, the default font size was set to 8.