Removing maven-junit-plugin as it does not support JUnit 4 and Surefire has parallel testing features.
Merge branch 'master' into no-maven-junit-plugin

Conflicts:
	pom.xml
	test/pom.xml
Merge branch 'master' into no-maven-junit-plugin

Conflicts:
	pom.xml
	test/pom.xml
Some missing sysprops.
Merge branch 'master' into no-maven-junit-plugin

Conflicts:
	test/pom.xml
Do not leave interactiveBreak in committed tests.
Baseline usage of Surefire 2.13.
Enabling reusable forked multithreading (4 threads seems good).
Seems to be roughly a few percent faster than maven-junit-plugin baseline.
Merge branch 'master' into no-maven-junit-plugin

Conflicts:
	pom.xml
Merge branch 'master' into no-maven-junit-plugin
Merge branch 'master' into no-maven-junit-plugin
systemPropertyVariables preferred to systemProperties and makes for smaller diff.
Merge branch 'master' into no-maven-junit-plugin
JUnit 4 broadly supported; no reason to keep a separate junit4 root just for UseRecipesWithJenkinsRuleTest.
Merge branch 'master' into pull-667
output to file