Fit a block of text into the current rectangle on the current
This function is similar to AddText
but can be used in situations in which you have a set area into
which you know your text should be fitted. The call will take the
base text supplied and scale it appropriately until it fits as
exactly as possible into the current Rect.
For fitting multi-styled text you should use the FitHtml method which is used for adding HTML styled text.