Change to more literal binding of freetype-gl.

This causes us to lose the multi-line functionality originally
introduced in the FreeTypeGL package. However, for most uses of
multiline layout, we will want to be using more expensive and accurate
layout functions. In these cases, it makes more sense to render to a
texture using something like pango, and then simply render the texture
in OpenGL.

Complex text will often also make use of many more fonts, or fonts with
many glyphs (CJK fonts) than would fit into a texture atlas of
reasonable size.
Rename package to 'electrotype'.

It has diverged too far from FreeTypeGL.