removed getElementValue from the Commands module

  - this method will be deprecated in the JsonWireProtocol
    soon.  the method will be retained in the WebElement module
    that simply makes a call to get_attribute('value')

lib/Selenium/Remote/Commands.pm

@@ -136,10 +136,6 @@ sub new {
               'method' => 'POST',
               'url' => "session/:sessionId/element/:id/submit"
         },
-        'getElementValue' => {
-               'method' => 'GET',
-               'url' => "session/:sessionId/element/:id/value"
-        },
         'sendKeysToElement' => {
                'method' => 'POST',
                'url' => "session/:sessionId/element/:id/value"