Fixing entities

1) thanks for verbosity hint
2) asked sat6 devs, most of the names are char[255], meaning, that if using utf, that has wider characters, generated names needs to be much smaller, so changing to 100

Dropping data like this is OK, but make sure to run the relevant test suites first. You can do so with `nosetests -c robottelo.properties tests/foreman/api/test_{host,model,organization,operatingsystem}_v2.py` or `python -m unittest tests.foreman.api.test_{host,model,organization,operatingsystem}_v2`.