grammar?

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@278459 13f79535-47bb-0310-9956-ffa450edef68

docs/manual/CoreTasks/signjar.html

@@ -20,7 +20,7 @@ directory or explicit JAR file name is not provided, JARs are signed in place.
 Dependency rules
 </p>
 <ul>
-<li>Nonexist destination JARs are created/signed</li>
+<li>Nonexistent destination JARs are created/signed</li>
 <li>Out of date destination JARs are created/signed</li>
 <li>If a destination file and a source file are the same,
 and <tt>lazy</tt> is true, the JAR is only signed if it does not