- Removed warning about exception classes having a base class with a protected...

- Removed warning about exception classes having a base class with a protected copy constructor (jira# 1323)
- Added placement new and delete to allow XMemory-derived classes to be hosted in STL containers


git-svn-id: https://svn.apache.org/repos/asf/xerces/c/trunk@176295 13f79535-47bb-0310-9956-ffa450edef68