new customActionOnZoomEvent for Zoom Event

as subject.
new customActionOnZoomEvent for Zoom Event

as subject.
another custom action for customActionOnMoveEvent

as subject.
another custom action for customActionOnMoveEvent

as subject.
Example that adds legend to the layerTree

Sample Customization.js that adds legend to the layerTree. Compatible only with QGIS 2.6
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Merge pull request #109 from luca76/master

Two new custom action functions.