Add an entity to the cache, only if it does not already exist.

Declaration Syntax

Parameters
- entity (Entity)
- The entity.
- expiry (TimeSpan)
- The interval after which the entity expires and
is removed from the cache.
Assembly: Mindscape.LightSpeed (Module: Mindscape.LightSpeed) Version: 1.2.1393.0 (1.2.1393.0)