Re-purpose fonts example (cmdline viewing tool)

The fonts example is now a command-line tool with user-cusotmizable
font rendering options for viewing what text rendering looks like
using the nom::Font interface.

* Text: Fix the non-power-of-two enumeration value of
Text::Style::Normal (default) -- from one (1) to zero (0).

* TrueTypeFont.hpp: Make note of the broken method
TrueTypeFont::set_hinting.

* TrueTypeFontTest: Add dialog pop up informing the end-user of how to
use the InteractiveGlyphCache test.
Remove examples/fonts/Resources
Rename fonts example to renderfont