* excluded oss-fuzz related CMake targets from all
* checkstl.cpp: fixed -Wmissing-declarations warning
* suppress -Wsuggest-attribute=format GCC warnings for tinyxml in CMake for now
* aligned GCC warnings in dmake, CMake and Travis / removed now useless WARNINGS_ANSI_ISO
* cleaned up oss-fuzz targets / use LIB_FUZZING_ENGINE for actual client
* fixed some compiler warnings in oss-fuzz sources
* only build the fuzz-client in Travis
* make fuzz-client CMake target work with CMake < 3
* fixed compilation of OSS-Fuzz clients
* added preliminary CMake target for fuzz-client - also added *_sanitized targets of dependencies (only available with Clang)
* added oss-fuzz build to Travis CI