[Unit Tests] RelationshipsMatrix should return unmodifiable Map types
[Unit Tests] TreeModelViewerDragDropHandler refactor and Unit Test overkill
[Unit Tests] MRUMenuManager refactor and Unit Tests
[Unit Tests] StringUtils: add compareVersionNumbers() method and tests
[Unit Tests] CheckForNewVersionAction refactor and Unit Tests
[Unit Tests] ModelCompatibility uses StringUtils.compareVersionNumbers()
[Unit Tests] Some corrections to tests and tested objects
[Unit Tests] Add DiagramModelUtils and Nested Relations tests

* Also upgrade ArchimateTestModel for more utils
[Unit Tests] Add DeleteCommandHandlerTests
Merge branch 'unit-tests'
Bump version number to 2.7.1
mvnization - sorta
Updated the docs for the selection tools in three places to make it
clearer how they work, and the relation between the alignment tools
and the primary selection.
Merge branch 'help-clarify-selection'
mvn and debian build
relative path for parent of test projects
Merge remote-tracking branch 'archi/develop' into mvn
fixup: version
user.home
fixup: extras download for travis