One very minor confusion in Audacity's Save/Export can arise because the
"Save Project" and "Save Compressed Project" save file dialog have the exact
same dialog title ("Save Project As...").
Since we are a have a test in the dialog constructor to determine if we are
going to save compressed or not, I propose that we conditionally change the
dialog title and the use "Save Compressed Project As..." when appropriate.
The attached patch adds a few lines of code to accomplish this.