`mexec-86` integration test fails at TravisCI

[kevstigneev]

mexec-86 integration test consistently fails at TravisCI with the following outout:

[INFO] Building: mexec-86/pom.xml
[INFO] run script verify.groovy
[INFO] ..FAILED (6.0 s)
[INFO]   The post-build script did not succeed. expected:<5> but was:<6>

Looks like it's something specific to the build environment because nobody has reproduced it locally - it just succeeds.

All TravisCI builds since Feb 26 2018 failed due to that. It affected PRs #95, #96, #97, #98, #100, #104, #110.

[rfscholte]

Not an issue anymore, both https://travis-ci.org/mojohaus/exec-maven-plugin and https://ci.appveyor.com/project/khmarbaise/exec-maven-plugin are green again