New widget : UnixPrintDialog
Add new dialog : PageSetupUnixDialog (you need to uncomment it before using it)
Add new widgets : PageSetup, PrintSettings, PaperSize
New widget : RecentChooserDialog (and all its subwidgets)
Update to last rust compiler version
Merge pull request #47 from GuillaumeGomez/master

Finalize dialog widget collections + update to last Rust ( str::raw -> string::raw )