Ant should not depend on tasks unless they are used.

PR: 217


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@267651 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/Project.java

@@ -127,6 +127,8 @@ public class Project {
                 try {
                     Class taskClass = Class.forName(value);
                     addTaskDefinition(key, taskClass);
+                } catch (NoClassDefFoundError ncdfe) {
+                    // ignore...
                 } catch (ClassNotFoundException cnfe) {
                     // ignore...
                 }