public static String getPluginRelativePath(PluginCoordinates coordinates) {
        StringBuilder pluginRelativePath = new StringBuilder();
        pluginRelativePath.append(coordinates.getGroupId());
        pluginRelativePath.append("/"); //$NON-NLS-1$
        pluginRelativePath.append(coordinates.getArtifactId());
        pluginRelativePath.append("/"); //$NON-NLS-1$
        pluginRelativePath.append(coordinates.getVersion());
        pluginRelativePath.append("/"); //$NON-NLS-1$
        pluginRelativePath.append(coordinates.getArtifactId());
        if (coordinates.getClassifier() != null) {
            pluginRelativePath.append("-").append(coordinates.getClassifier()); //$NON-NLS-1$
        }
        pluginRelativePath.append("."); //$NON-NLS-1$
        pluginRelativePath.append(coordinates.getType());
        return pluginRelativePath.toString();
    }
Returns the relative path (within a plugin registry's plugins directory) where
the plugin with the given coordinates can be found.  For example, if the plugin
coordinate are "io.apiman.sample:sample-plugin:1.0.1:classifier:war" then the
path will be:

io.apiman.sample/sample-plugin/1.0.1/sample-plugin-classifier.war/

@param coordinates the coordinates
@return plugin's relative path
common/plugin/src/main/java/io/apiman/common/plugin/PluginUtils.java