[Ayatana] transparent Ayatana Indicators

["frederik.nnaji@xxxxxxxxx" <frederik.nnaji@xxxxxxxxx>]

Imagine:
Ayatana Indicators are semi-transparent technical symbols above the application window top right corner edge.

They are:
* opaque, if no application window is focused
* opaque if the desktop is focused

* silhouette when application window is focused
* dim-fade silhouette whenever idle > 10 sec

the visual design would result in a type of transparent dimming effect, since we are working with monochrome color. Symbolic icons have the great advantage, that they behave like shapes more than anything else, it is easier for the human mind to interpret them as simple physical objects, or even electric elements. Increased or decreased opacity on a symbol behave like increased and decreasing saturation, as long as the symbol is visible.

If we want to give any transparency control widget any sense at all, we should ban full transparency, fix a lower limit for transparency and add a checkbox to dematerialize/close/dissolve/delete the item completely, instead of offering a nonesensical range of transparency below the fixed minimum, which would have none but dissipating use cases..