(HI-289) expand Hiera basic functionality acceptance tests
  three tests added:
  lookup_data_no_options tests a simple priority lookup of a string from
    CLI
  default_value_if_key_not_found tests that default value is used when
    key not found from CLI
  check_first_backend_hierarchy_first test multiple backends to ensure
    each hierarchy is checked in order as in the config file

(HI-289) expand basic functionality tests to work in windows and
solaris11.
make tests more atomic

(HI-289) refactor tests based on feedback from John and Kurt.
reduce windows conditionals and namespace use.
eliminate possible namespace collision with agent object.