Text Rendering

[winksaville]

I was experimenting with csgrs text rendering and ran into some issues and I'd like to suggest two changes.

1. Add a character spacing parameter as a scale or as a value in system coordinate units so that characters are rendered "properly", below we see there are no spaces between the "HHI" characters.

2. Instead of using passing scale pass height in system coordinate units. This makes it much simpler than having to figure out a the scale the unstated relationship between scale and physical height. It also solves issues with the bounding box height changing with different characters in a font.

See csgrs-text for details

[timschmidt]

Clearly some issues to work out still in the transition away from meshtext, to translating ttf paths into geo linestrings. I think your suggestion to make scale an absolute height unit is a good one.