Draft: Update Template's Get() methods for easier object access

Uses accessor (godoc, source) from the meta package to access attributes of a generic object of type *runtime.Object.

Also adds "app" label to testdata chart to match what we use in the GitLab Helm chart so it can be tested appropriately.

Enables us to easily pull objects with the following methods:

• GetObjectByNameAndKind
• GetObjectsByKind
• GetObjectsByKind
• GetObjectsByChart
• GetObjectsByChartAndKind

Closes #33 (closed)