[OPENENGSB-3776] better support for xlink switch
Merge pull request #916 from stfnsche/xlink

[OPENENGSB-3776] better support for xlink switch
[OPENENGSB-3776] fix checkstyle errors
Merge pull request #917 from stfnsche/xlink

[OPENENGSB-3776] fix checkstyle errors
[OPENENGSB-3776] provide means to call openXLinks
Merge pull request #918 from stfnsche/xlink

[OPENENGSB-3776] provide means to call openXLinks
update root, domain-parent and conenctor-parent version
update CHANGELOG for the 3.0.0.M2 release
update connector-parent version