incremental updates for building trunk on MSVS 2013 C++

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13535 47890b92-0858-11df-a26f-8b716316a5bc
Round 3 of realtime changes.

This gets meter type VST effects working again by extending the

The master now maintains his own internal buffers and sums (mixes) all
playing tracks into those buffers.  The buffers are then fed into the
VST effect that is presented to the user.  This allows the effect to
provide feedback to the user if it support it.  Such effects may display
meters or clipping indicators.

Several issues with treading have also been corrected (hopefully ;-)).
These showed up mostly on Linux, but could have happened on the others
as well.

The realtime support is no longer limited to 2 channels per logical
track.  Once support for more channels is added, this should be ready
for it.

The rack dialog can now be toggled via the edit toolbar button.  It
doesn't stay pressed because the closing of the dialog would have to
be communicated back to the toolbar.

As the rack is updated with new or removed effects or active state
changed, all effects in the active list were shutdown and all effects
in the updated list were initialized.  This now shuts down only the
effects no longer in the list and initializes only new ones.

The rack now uses wxBitmapButton instead of Audacity's AButton.  The
AButton has a timing issue that prevents it from being deleted while
processing the click event.  I looked into it, but gave up and switched
to the wxBitmapButton.  Unfortunately, there's a problem with the
wxBitmapButton as well...at least on my setup here.  Either the bitmaps
are being scaled or antialiased.  Will have to get feedback on this.

I finally figured out why some VSTs didn't seem to do anything in
realtime, at least in my case anyway.  I've installed a lot of demo
VSTs and while they work in "batch/offline" mode, some of them will
not work in realtime since vendors tend to remove automation as one
of the demo limitations.

More changes coming shortly...



git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13536 47890b92-0858-11df-a26f-8b716316a5bc