Bootstrap integration tests should fail the build if **any** Spine library is not compatible with each other #57
Description
While the bootstrap plugin is the entry point for developers into the Spine world, we should be 100% sure that a particular bootstrap plugin version holds Spine libraries versions that are compatible with each other.
The only way to achieve that I see is to create a comprehensive set of integration tests with various scenarios handled in the tests.
The reasoning behind the issue is that the current version of the plugin (v1.6.21) has incompatible base and core versions.