Volume Density

A group of two indicators:
The "Volume Density" shows how much volume was thrown out relative to the covered price range.
The "Volume Density Bars" shows the same, but with colour on top of the bar chart.

Versionshinweise:

Merge with "Volume Density Bars" by adding option to colourize bars and disable histogram.

Versionshinweise:

Add option to select a moving average function

Versionshinweise:

Add clip value setting to clip spikes of high volume

Versionshinweise:

Fix priveiw image

Versionshinweise:

Fix "Invalid symbol" warning when the custom volume source is enabled.