added missing include for clang
added <stdexcept> include for clang
 * added a lot of #include <stdexcept>
Merge branch 'master' of https://github.com/jklimke/libcitygml

# By jklimke
# Via jklimke
* 'master' of https://github.com/jklimke/libcitygml:
  added <stdexcept> include for clang
  added missing include for clang