Add some trivial Herald related PhpDoc comments

Summary: Self-explanatory.

Test Plan: Read and play with code.

Reviewers: O1 Blessed Committers, valerio.bozzolan

Reviewed By: O1 Blessed Committers, valerio.bozzolan

Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno

Differential Revision: https://we.phorge.it/D25884

src/applications/herald/action/HeraldAction.php

@@ -122,6 +122,9 @@ abstract class HeraldAction extends Phobject {
     return $this;
   }
 
+  /*
+   * @return HeraldAdapter HeraldAdapter class of the action
+   **/
   final public function getAdapter() {
     return $this->adapter;
   }

src/applications/herald/engine/HeraldEffect.php

@@ -13,6 +13,9 @@ final class HeraldEffect extends Phobject {
     return $this;
   }
 
+  /**
+   * @return string PHID of the object that Herald is applied on
+   */
   public function getObjectPHID() {
     return $this->objectPHID;
   }
@@ -22,6 +25,9 @@ final class HeraldEffect extends Phobject {
     return $this;
   }
 
+  /**
+   * @return string ACTIONCONST of the HeraldAction
+   */
   public function getAction() {
     return $this->action;
   }
@@ -31,6 +37,9 @@ final class HeraldEffect extends Phobject {
     return $this;
   }
 
+  /**
+   * @return array|null
+   */
   public function getTarget() {
     return $this->target;
   }
@@ -40,6 +49,9 @@ final class HeraldEffect extends Phobject {
     return $this;
   }
 
+  /**
+   * @return HeraldRule
+   */
   public function getRule() {
     return $this->rule;
   }
@@ -49,6 +61,10 @@ final class HeraldEffect extends Phobject {
     return $this;
   }
 
+  /**
+   * @return string Reason why Herald effect was applied, for example
+   *         "Conditions were met for H123 RuleName"
+   */
   public function getReason() {
     return $this->reason;
   }

src/applications/herald/storage/HeraldRule.php

@@ -265,6 +265,9 @@ final class HeraldRule extends HeraldDAO
       ->addString($this->getName());
   }
 
+  /**
+   * @return string Name of the rule, for example "H123 RuleName (Disabled)"
+   */
   public function getEditorDisplayName() {
     $name = pht('%s %s', $this->getMonogram(), $this->getName());