Merge pull request #484 from cquinn/master

Fixed grammatical error in build page message.
Thnaks!

core/src/main/resources/hudson/model/AbstractBuild/index.properties

 # The MIT License
-# 
+#
 # Copyright (c) 2004-2009, Sun Microsystems, Inc., Kohsuke Kawaguchi
-# 
+#
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
 # in the Software without restriction, including without limitation the rights
 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 # copies of the Software, and to permit persons to whom the Software is
 # furnished to do so, subject to the following conditions:
-# 
+#
 # The above copyright notice and this permission notice shall be included in
 # all copies or substantial portions of the Software.
-# 
+#
 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
@@ -21,4 +21,4 @@
 # THE SOFTWARE.
 
 startedAgo=Started {0} ago
-beingExecuted=Build is being executed for {0}
\ No newline at end of file
+beingExecuted=Build has been executing for {0}