adjusted naming

Author: StefanSpieker

src/main/resources/io/jenkins/plugins/designlibrary/Validation/index.jelly

@@ -30,7 +30,7 @@
       <s:group>
         <s:preview>
           <form method="post">
-            <f:entry title="${%Positive integer}">
+            <f:entry title="${%Non-negative integer}">
               <f:number min="0" clazz="number"/>
             </f:entry>
           </form>

src/main/webapp/Validation/sample-clazz.jelly

@@ -1,3 +1,3 @@
-<f:entry title="${%Positive integer}" field="name">
+<f:entry title="${%Non-negative integer}" field="name">
   <f:number min="0" clazz="number"/>
 </f:entry>