Fixed AR-1321: Allow '&' in filename

The following filename is valid now: "x ¬ £ % & + ; x.txt"
This was a restriction imposed by WebDAV, but the encoding of the repsonses is working well and these restrictions be removed as a result.

Fixed AR-1281: WebDAV upload was assigning incorrect encoding

I added a bean 'charset.finder', which can be fetched from the MimetypeService.
Various pluggins now exist to decode a stream and figure out what the encoding is.
WebDAV and CIFS/FTP are now hooked into this so that they guess a little better.

Fixed others:
Added retrying transactions to WebDAV.
Read/write transactions for WebDAV.


git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@6073 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/repo/webdav/OptionsMethod.java

@@ -69,6 +69,15 @@ public class OptionsMethod extends WebDAVMethod
         // Nothing to do in this method
     }
 
+    /**
+     * @return          Returns <tt>true</tt> always
+     */
+    @Override
+    protected boolean isReadOnly()
+    {
+        return true;
+    }
+
     /**
      * Perform the main request processing
      *