Improvement #135
+ create test to verify wrong behaviour
Improvement #135
* rename ModuleDirectoryFactroy to *Factory
Improvement #135
+ changed behaviour: target folders are now marked HIDDEN and FORBIDDEN
* fixed error in computation of derived files
Feature #123 Ability to skip b2 bootstrapper
+ added -DskipB2 and integration test
#137: Decoupled B2MavenBridge from Maven Session lifecycle (-> b2 no
longer required as build extension during tycho build)
Merge branch 'pu/136-tycho-0.21.0'
Merge branch 'pu/135-delete-maven-target-only-if-clean'
Merge branch 'pu/123-ability-to-skip-b2-bootstrapper'
Merge branch 'pu/137-no-build-ext'
#138: Apache License Version 2.0
Conflicts:
	b2-integration-tests/src/test/java/org/sourcepit/b2/its/DoNotRemoveTargetFolderIT.java
	b2-integration-tests/src/test/java/org/sourcepit/b2/its/ManifestFilterIT.java
	b2-integration-tests/src/test/java/org/sourcepit/b2/its/SkipB2IT.java
	b2-integration-tests/src/test/java/org/sourcepit/b2/its/util/FilePresentMatcher.java
	b2-integration-tests/src/test/resources/DoNotRemoveTargetFolderIT/module.xml
	b2-integration-tests/src/test/resources/DoNotRemoveTargetFolderIT/submodule/module.xml
	b2-integration-tests/src/test/resources/SkipB2IT/module-a/module.xml
	b2-integration-tests/src/test/resources/SkipB2IT/module-b/module.xml
	b2-integration-tests/src/test/resources/SkipB2IT/module.xml
	b2-integration-tests/src/test/resources/SkipB2IT/modules-parent/module.xml
	b2-integration-tests/src/test/resources/SkipB2IT/pom.xml
	b2-maven-core/src/test/java/org/sourcepit/b2/maven/core/B2MavenBridgeTest.java
	b2-maven-release-manager/src/test/java/org/sourcepit/b2/release/phase/CompatibilityTest.java
	b2-model-builder/src/main/java/org/sourcepit/b2/internal/generator/B2Generator.java
	b2-model-builder/src/test/java/org/sourcepit/b2/files/ModuleDirectoryTest.java
	pom.xml
prepared release