Remove hardcoded execution environment

This change accidentally got added in my previous commit.  I was trying to see if there was a way we could parameterize this classpath entry.  Something like this:
```
<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/_ee_"/>
```
Where _ee_ would be expanded out to whatever the developer had set in the enroute.bnd file
```
-runee: JavaSE-1.7
```
Then whatever was there would be expanded in the .classpath files.