0.3.1

Prevent system registration from overwriting existing entity list.

0.3.0

Add tag system that processes entities by tag.

0.2.6

Replace internal event listener with miru gem.

0.2.5

Add has_component? to Entity.

0.2.4

Add world disposal.

0.2.3

Separate entity retrieval and processing logic in system to allow pre and post-processing.

0.2.2

Fix entities being added to entity manager multiple times.

0.2.1

Restore system access to world delta_ms.

0.2.0

Add ability to remove components from an entity.
Extract component mask logic into its own class.
Remove a few instances of unnecessary coupling.
Write remaining tests.

0.1.0

Initial release!