Cleanup Mylyn Releng

[BeckerFrank]

Actual we have the following two projects.

1. org.eclipse.mylyn/org.eclipse.mylyn.releng.
   here we have in one project all the following

• OOMPH Setup
• launcher Definition
• some helper Shell Scripts
• an outdate no longer maintained local Test environment using vagrant
• an new not fully finished local Test environment using Multipass and Docker
• a folder .setting which can be used as a source for apply settings to all projects

2. org.eclipse.mylyn/mylyn.releng
   in this folder we actual only have this product

• org.eclipse.mylyn.parent
  used for the Maven Builds