Add release note for BOSH release [PR #43](concourse/concourse-bosh-release#43]
#### <sub><sup><a name="v560-note-4442" href="#v560-note-4442">:link:</a></sup></sub> fix
* `/opt/resource/out` scripts in resources could previously crash `atc` instances by outputing `null` to `stdout`, causing a nil pointer dereference. The `atc` now checks for a nil value and, if one is found, returns before dereferencing the pointer. #4442
+
+#### <sub><sup><a name="v560-note-43" href="#v560-note-43">:link:</a></sup></sub> feature
+
+* @joshzarrabi and @aemengo added `CONCOURSE_GARDEN_MAX_CONTAINERS` as configurable flag in BOSH release.
+ Defaults to 250. Please note that setting this limit over 250 has not been tested by the Garden team or the Concourse team. [#43](concourse/concourse-bosh-release#43).
