Starter archetype pipeline has no runner on its classpath

When generating a new maven project using the starter archetype, the pipeline does not execute because it doesn't have a runner jar on it's classpath:

$ mvn exec:java -Dexec.mainClass=swegner.StarterPipeline
...
[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.4.0:java (default-cli) on project yo: An exception occured while executing the Java class. null: InvocationTargetException: No Runner was specified and the DirectRunner was not found on the classpath.

In the examples archetype, we have the direct runner as a dependency. We should do the same for the starter archetype.

Imported from Jira [BEAM-1032](https://issues.apache.org/jira/browse/BEAM-1032). Original Jira may contain additional context.
Reported by: swegner.

Inspect the starter archetype's Maven dependency configuration and compare it with the examples archetype, which includes the DirectRunner dependency. Run `mvn exec:java -Dexec.mainClass=swegner.StarterPipeline` with a generated project and verify that the pipeline starts without the missing-runner error.

Written by the indexing model from the issue text.