Fix wrong boolean handling

src/Phing/Parser/TargetHandler.php

@@ -137,7 +137,7 @@ public function init($tag, $attrs)
                     break;
 
                 case 'hidden':
-                    $isHidden = ('true' === $value || '1' === $value);
+                    $isHidden = StringHelper::booleanValue($value);
 
                     break;
 

src/Phing/Type/Selector/ModifiedSelector.php

@@ -253,11 +253,11 @@ public function useParameter(Parameter $parameter): void
         } elseif ('comparator' === $key) {
             $this->setComparator($value);
         } elseif ('update' === $key) {
-            $this->setUpdate('true' === strtolower($value));
+            $this->setUpdate(StringHelper::booleanValue($value));
         } elseif ('delayupdate' === $key) {
-            $this->setDelayUpdate('true' === strtolower($value));
+            $this->setDelayUpdate(StringHelper::booleanValue($value));
         } elseif ('seldirs' === $key) {
-            $this->setSeldirs('true' === strtolower($value));
+            $this->setSeldirs(StringHelper::booleanValue($value));
         } elseif (StringHelper::startsWith(self::CACHE_PREFIX, $key)) {
             $name = StringHelper::substring($key, strlen(self::CACHE_PREFIX));
             $this->tryToSetAParameter($this->cache, $name, $value);