Fix jme3-documentation: Specify javax.help from mavenCentral as dependency, as it doesn't ship with netbeans anymore

build.gradle

@@ -18,6 +18,7 @@ repositories {
     jcenter {
         url "http://jcenter.bintray.com/"
     }
+    mavenCentral()
     maven {
         url "http://updates.jmonkeyengine.org/maven/"
     }
@@ -81,6 +82,7 @@ dependencies {
 
     corelibs dep("com.github.xbuf:jme3_xbuf:0.9.1", false, false)
     corelibs dep("com.badlogicgames.gdx:gdx-ai:1.8.1", true, true)
+    corelibs dep("javax.help:javahelp:2.0.05", false, false)
 
     corelibs dep("org.jmonkeyengine:jme3-core:$jmeEngineVersion", true, true)
     corelibs dep("org.jmonkeyengine:jme3-desktop:$jmeEngineVersion", true, true)

jme3-documentation/nbproject/project.xml

@@ -6,6 +6,15 @@
             <code-name-base>com.jme3.gde.docs</code-name-base>
             <suite-component/>
             <module-dependencies>
+                <dependency>
+                    <code-name-base>com.jme3.gde.core.libraries</code-name-base>
+                    <build-prerequisite/>
+                    <compile-dependency/>
+                    <run-dependency>
+                        <release-version>1</release-version>
+                        <specification-version>3.3.0</specification-version>
+                    </run-dependency>
+                </dependency>
                 <dependency>
                     <code-name-base>org.netbeans.modules.javahelp</code-name-base>
                     <build-prerequisite/>