Add text_font_filters example

[RobLoach]

Cleaned it up a bit with...

• Removed the position, as there are a few different Draw() method patterns. And the other classes don't use the position.
• Added text_font_filters as an example which uses it
• Made use of the GETTERSETTER utility for the properties
• Updated with initializer lists
• Made the properties public, as the other classes don't really restrict accessing them

Overall, I like having Text, and think we could add some of the other Text methods in here too.