Add bundle changes to release notes

[gtkramer]

As a part of release note generation, bundle changes for the local bundles added to the mix should be shown. This means showing added, updated, and removed bundles. For now, this should only apply to the bundles for the particular distribution. If a downstream, it should not show changes for upstream bundles. While an improvement for the future, these may be resolved by looking at the release notes of the upstream on which the distribution is bases.