[REF] DAO - Make getEntityIcon() function more useful

[colemanw]

Overview

Makes getter function work all the time, not just when passed an id.

Before

No general getter function for DAO_*::$_icon, which requires direct access to internal class variable.
BAO:getEntityIcon() only works when passed an id.

After

BAO:getEntityIcon() works as a getter function both for a specific entity, and also for the entity in-general.

[civibot]

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