Draw dotted lines on frequency selection.

Patch from Paul Licameli, but simplified.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13477 47890b92-0858-11df-a26f-8b716316a5bc
Fix my regression in previous patch: Edges on grayscale should be white, not black.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13478 47890b92-0858-11df-a26f-8b716316a5bc
Allow all output from Nyquist Prompt effect.
As the Nyquist Prompt is the only direct access to input Nyquist commands, it needs to remain flexible and versatile.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13479 47890b92-0858-11df-a26f-8b716316a5bc
Now have three varieties of the Meter Toolbar.

We have separate record and play meters.  The original kind of meter is now called a combined meter.  I've kept it because it can be useful when undocked if you do want both meters.  I've also fixed it so that if made very narrow the meters stack vertically just as they already did horizontally.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13480 47890b92-0858-11df-a26f-8b716316a5bc
Fixed some memory leaks.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13481 47890b92-0858-11df-a26f-8b716316a5bc
Fixed docking of large toolbars.

Previously there were three problems:
1) Docking marker calculation was relative to the mouse rather than relative to the top left of the dragged toolbar.  On a big toolbar dragged from the bottom of the dragger that could be a long way off.
2) Docking markers appeared too low down.  Their position was relative to the middle of the dragged toolbar.  However as the toolbar may be resized on placement that does not make sense.
3) Large (Height()>120) toolbars could be thought to be too tall to dock in some places.  The positioning code used their current size rather than their minimum size.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13482 47890b92-0858-11df-a26f-8b716316a5bc
Spectral selection effects now prompt for missing frequency fields when used in time selection mode.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13483 47890b92-0858-11df-a26f-8b716316a5bc
Fix: With no prior config set show Record and Play meter, don't show Combined meter.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13484 47890b92-0858-11df-a26f-8b716316a5bc
Meters now linear by default.

Done following on from comments and +1's on the wiki page about the meters.

git-svn-id: http://audacity.googlecode.com/svn/audacity-src/trunk@13485 47890b92-0858-11df-a26f-8b716316a5bc