Pulled the hardcoded "encoding" out of the document itself and made it a #define

to make it easier to support other encodings.  Patch from David McCreedy.
And other modification for consistent help display and return code across samples.


git-svn-id: https://svn.apache.org/repos/asf/xerces/c/trunk@173138 13f79535-47bb-0310-9956-ffa450edef68