refactor: move ofTtfSettings into ofTrueTypeFont

[tgfrerer]

• following the same pattern we use with ofFbo and other objects

Example: Create a Settings object, and pass it to load() - here we are instructing an Icon font to load specific unicode ranges:

ofTrueTypeFont myFont;

ofTrueTypeFont::Settings settings("MaterialIcons-Regular.ttf", 26);
settings.antialiased = true;
settings.addRange({0xe889,0xe889}); // history
settings.addRange({0xe034,0xe039}); // play/pause buttons

myFont.load(settings);

The hope is to make the Settings object more discoverable, which should help especially with IDEs that have code completion.

[arturoc]

This seems to be failing cause ofxGui is using the previous syntax

[tgfrerer]

I've updated ofxGui - also grep'ed examples and addons to see if there were any other uses of ofTtfSettings - seems the 4 locations in ofxGui is all. I've updated the CHANGELOG for good measure.

[arturoc]

thanks!!