Fix behaviour if examples are used with composite steps

[jsedlace]

We use plenty of scenarios with Example tables and composite steps and bad enumeration of children for examples caused strange NPE in some jUnit4 classes, which then failed the mvn build.

[jsedlace]

I've just found out that manifestations of the error we met were fix in 8ceeda6, but this PR should solve the root cause.

[coveralls]

Coverage increased (+0.05%) to 92.925% when pulling f8c148a on WanderaOrg:fix-examples-with-composite-steps into 6f00f27 on valfirst:master.

[valfirst]

@jsedlace, thank you for contribution

[jsedlace]

@valfirst When you plan to do next release/can you release today or tomorrow?

[valfirst]

@jsedlace, I will release a new version today (in 1-2 hours)

[valfirst]

@jsedlace, new release is published (http://repo1.maven.org/maven2/com/github/valfirst/jbehave-junit-runner/2.1.2/):

<dependency>
    <groupId>com.github.valfirst</groupId>
    <artifactId>jbehave-junit-runner</artifactId>
    <version>2.1.2</version>
</dependency>