correct wrong parameters format order in core-default.xml

descriptions of "HTTP CORS" parameters is before the names:
<property>
<description>Comma separated list of headers that are allowed for web
services needing cross-origin (CORS) support.</description>
<name>hadoop.http.cross-origin.allowed-headers</name>
<value>X-Requested-With,Content-Type,Accept,Origin</value>
</property>
..........
but they should be following value as others.