Is your enhancement related to a problem? Please describe.

I often need to link to concrete che property to link it to someone. There is nice generated page in che docs with all properties https://www.eclipse.org/che/docs/che-7/installation-guide/advanced-configuration-options-for-the-che-se

Document the commands that clients should implement and their expected behaviour on https://github.com/eclipse/eclipse.jdt.ls/wiki/JDT-LS-Extensions

Consider the following:

void meth(Closure closure) {
  closure.|
}

When invoking content assist (Ctrl+Space) at |, the methods and properties of groovy.lang.Closure are very low in the list of proposals. This is due to very-well-known type adjustments made within org.codehaus.groovy.eclipse.codeassist.proposals.AbstractGroovyProposal.getRelevanceClass().

Following the instructions on page
https://github.com/eclipse/sprotty/wiki/Running-the-examples
(either with master or 0.9.0 tag)
When I go to http://127.0.0.1:8080 with my browser (Firefox, Chrome, even tried with IE), I get an error page.
Looks like there is an invalid redirection. Firefox says the request can't succeed ("La requête ne peut aboutir" in french), Chrome says "ERR_INVALID_REDIR