change Audio Format for Project -> 44/48/96 Khz

[OeAi]

Sometimes there's a need to convert whole project to a supported Sample Rate of a card and i can convert project bit depth in utilities, but i would also add there a sample rate change, so all audio files of a project should be converted (or rebounced) and actual sample rate should be changed.

In fact i think that it should be done automatically if sample rate is not the same as it is set in current Cakewalk setup, so the dialog should appear with opening project.