Add more detailed instruction on how to use this

[mojo2012]

HI there,

I tried to follow the instructions but regardless in which folder I run mvn package, I get meaningless errors - nothing works so far.

I added this to my releng/repo.config/pom.xml:

<eclipse-launcher.url>https://resheim.net/p2/eclipse-launcher/</eclipse-launcher.url>
<decompiler.url>https://ecd-plugin.github.io/update/</decompiler.url>
<workspace-refresher.url>https://dl.bintray.com/ugrave/com.github.ugrave/</workspace-refresher.url>

...
<repository>
	<id>eclipse launcher</id>
	<url>${eclipse-launcher.url}</url>
	<layout>p2</layout>
</repository>
<repository>
	<id>decompiler</id>
	<url>${decompiler.url}</url>
	<layout>p2</layout>
</repository>
<repository>
	<id>workspace refresher</id>
	<url>${workspace-refresher.url}</url>
	<layout>p2</layout>
</repository>

I copied releng/eclipse-cdt.product to releng/eclipse-core.product and renamed all cdt occurrences to core both in the pom.xml and in the eclipse-core.product.

Furthermore I added this to the features section:

<feature id="org.eclipse.jpt.jpadiagrameditor.feature.feature.group" />
<feature id="org.eclipse.jpt.jpa.feature.feature.group" />
<feature id="org.sf.feeling.decompiler.feature.group" />
<feature id="org.sf.feeling.decompiler.cfr.feature.group" />
<feature id="org.sf.feeling.decompiler.jad.feature.group" />
<feature id="org.sf.feeling.decompiler.jd.feature.group" />
<feature id="org.sf.feeling.decompiler.procyon.feature.group" />
<feature id="org.sf.feeling.decompiler.source.feature.group" />
<feature id="org.eclipse.m2e.feature.feature.group" />
<feature id="org.eclipse.m2e.logback.feature.feature.group" />
<feature id="net.resheim.eclipse.launcher.feature.group" />
<feature id="com.github.ugrave.tools.ws.refresh.feature.feature.group" />

And I added <module>eclipse-core.product</module> to releng/pom.xml.

Where should I run mvn package?
In the root?

[ERROR] [ERROR] Some problems were encountered while processing the POMs:
[FATAL] Non-readable POM /Users/matthias/Projekte/Git/custom-eclipse-ide/features/my-custom.feature/.polyglot.build.properties: input contained no data @
 @
[ERROR] The build could not read 1 project -> [Help 1]
[ERROR]
[ERROR]   The project  (/Users/matthias/Projekte/Git/custom-eclipse-ide/features/my-custom.feature/.polyglot.build.properties) has 1 error
[ERROR]     Non-readable POM /Users/matthias/Projekte/Git/custom-eclipse-ide/features/my-custom.feature/.polyglot.build.properties: input contained no data

In releng:

org.osgi.framework.BundleException: Could not resolve module: org.eclipse.equinox.registry [42]
  Unresolved requirement: Import-Package: org.eclipse.core.runtime.jobs; resolution:="optional"
    -> Export-Package: org.eclipse.core.runtime.jobs; bundle-symbolic-name="org.eclipse.core.jobs"; bundle-version="3.8.0.v20160209-0147"; version="0.0.0"
       org.eclipse.core.jobs [6]
         Unresolved requirement: Require-Bundle: org.eclipse.equinox.common; bundle-version="[3.8.0,4.0.0)"
           -> Bundle-SymbolicName: org.eclipse.equinox.common; bundle-version="3.8.0.v20160315-1450"; singleton:="true"
              org.eclipse.equinox.common [18]
                Unresolved requirement: Require-Capability: osgi.ee; filter:="(&(osgi.ee=JavaSE)(version=1.7))"
  Unresolved requirement: Require-Bundle: org.eclipse.equinox.common; bundle-version="[3.7.0,4.0.0)"
    -> Bundle-SymbolicName: org.eclipse.equinox.common; bundle-version="3.8.0.v20160315-1450"; singleton:="true"
...

in the releng/repo.conf folder the builds succeeds but it looks like it does nothing at all.

I hope you can help me out here :-D