Fix javadoc generation and some errors

- Generate javadoc containing all the classes from all submodules

.travis.yml

@@ -1,7 +1,7 @@
 language: java
 
 script: ./gradlew check
-after_success: ./gradlew javadoc
+after_success: ./gradlew aggregatedJavadocs
 
 deploy:
   provider: pages

build.gradle

@@ -29,3 +29,19 @@ subprojects {
     }
 }
 
+// https://discuss.gradle.org/t/best-approach-gradle-multi-module-project-generate-just-one-global-javadoc/18657/21
+task aggregatedJavadocs(type: Javadoc, group: 'Documentation') {
+    destinationDir = file("$buildDir/docs/javadoc")
+    title = "$project.name $version"
+    // options.memberLevel = JavadocMemberLevel.PRIVATE
+    options.links 'https://docs.oracle.com/javase/7/docs/api/'
+    
+    subprojects.each { project ->
+        project.tasks.withType(Javadoc).each { javadocTask ->
+            source += javadocTask.source
+            classpath += javadocTask.classpath
+            excludes += javadocTask.excludes
+            includes += javadocTask.includes
+        }
+    }
+}

extractor/src/main/java/org/schabi/newpipe/extractor/Extractor.java

@@ -9,7 +9,7 @@ import java.io.IOException;
 
 public abstract class Extractor {
     /**
-     * {@link StreamingService} currently related to this extractor.<br/>
+     * {@link StreamingService} currently related to this extractor.<br>
      * Useful for getting other things from a service (like the url handlers for cleaning/accepting/get id from urls).
      */
     private final StreamingService service;
@@ -20,7 +20,7 @@ public abstract class Extractor {
      * What makes a url "dirty" or not is, for example, the additional parameters
      * (not important as—in this case—the id):
      * <pre>
-     *     https://www.youtube.com/watch?v=a9Zf_258aTI<i>&t=4s</i>  →  <i><b>&t=4s</b></i>
+     *     https://www.youtube.com/watch?v=a9Zf_258aTI<i>&amp;t=4s</i>  →  <i><b>&amp;t=4s</b></i>
      * </pre>
      * But as you can imagine, the time parameter is very important when calling {@link org.schabi.newpipe.extractor.stream.StreamExtractor#getTimeStamp()}.
      */

extractor/src/main/java/org/schabi/newpipe/extractor/ListExtractor.java

@@ -26,7 +26,7 @@ public abstract class ListExtractor<R extends InfoItem> extends Extractor {
     public abstract InfoItemsPage<R> getInitialPage() throws IOException, ExtractionException;
 
     /**
-     * Returns an url that can be used to get the next page relative to the initial one.<br/>
+     * Returns an url that can be used to get the next page relative to the initial one.
      * <p>Usually, these links will only work in the implementation itself.</p>
      *
      * @return an url pointing to the next page relative to the initial page

extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/YoutubeStreamUrlIdHandler.java

@@ -119,7 +119,7 @@ public class YoutubeStreamUrlIdHandler implements UrlIdHandler {
      * Shared URI's look like this:
      * <pre>
      *     * https://www.youtube.com/shared?ci=PJICrTByb3E
-     *     * vnd.youtube://www.youtube.com/shared?ci=PJICrTByb3E&feature=twitter-deep-link
+     *     * vnd.youtube://www.youtube.com/shared?ci=PJICrTByb3E&amp;feature=twitter-deep-link
      * </pre>
      *
      * @param url The shared url