YAML.load is now interpreted as YAML.safe_load, which breaks where the
YAML file contains aliases. If we can assume our yaml files are
trusted (since this a development tool), we can check for the presence
of YAML.unsafe_load and use it instead if it exists.
Altered the rake build so that it passes. The example_3 shows off
some failing tests, so the rake build has to ignore those.
Update .gitignore file with executables from examples
