On svn-auth-x509 branch, Comply with the BSD license from TropicSSL.

* NOTICE,
  LICENSE: Add appropriate license information for the X.509 parser code.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/svn-auth-x509@1613535 13f79535-47bb-0310-9956-ffa450edef68