This removes the variables graphics.ntextbox, as well as removing
'active' from each text box object. Thus, all text boxes are really
real, and you don't have to check its 'active' variable.
Something that's slightly annoying is that in order to make the vector
of text boxes be properly used, the text box cannot remove itself.
Because the text box does not know it's in a vector. So move the removal
of the text box to drawgui() instead.
This uses utfcpp combined with a custom font, in the form of a PNG and text file. By default, the game acts exactly as it did before; custom fonts can be provided by third parties.
