Consider support for Spring Boot Test Slice Annotations

[jxblum]

For example: @ClientServerIntegrationTest

This will:

• Use conventions to determine the server-side configuration class (e.g. GeodeServerConfiguration, or simply ServerConfiguration), or...
• Perhaps use annotations (e.g. @ServerConfiguration) to declare the server's configuration.
• Start a GemFire/Geode Server with the declared configuration.
• ???