Fix some wrong implementations #12

Author: junichi11

src/main/java/com/junichi11/netbeans/modules/github/issues/issue/GitHubIssueProvider.java

@@ -109,12 +109,12 @@ public IssueController getController(GitHubIssue issue) {
     }
 
     @Override
-    public void removePropertyChangeListener(GitHubIssue issue, PropertyChangeListener listener) {
+    public void addPropertyChangeListener(GitHubIssue issue, PropertyChangeListener listener) {
         issue.addPropertyChangeListener(listener);
     }
 
     @Override
-    public void addPropertyChangeListener(GitHubIssue issue, PropertyChangeListener listener) {
+    public void removePropertyChangeListener(GitHubIssue issue, PropertyChangeListener listener) {
         issue.removePropertyChangeListener(listener);
     }