Test error when multinest is not installed

[migueldvb]

There is an error in test_fits when saving object data to HDF5 if multinest is not available:

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ERROR: isochrones.tests.test_fits.test_fitting
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Traceback (most recent call last):
  File "/usr/lib/python3.5/site-packages/nose/case.py", line 198, in runTest
    self.test(*self.arg)
  File "/home/miguel/Gaia/isochrones/isochrones/tests/test_fits.py", line 26, in test_fitting
    _check_saving(mod_dar)
  File "/home/miguel/Gaia/isochrones/isochrones/tests/test_fits.py", line 33, in _check_saving
    mod.save_hdf(filename)
  File "/home/miguel/Gaia/isochrones/isochrones/starmodel.py", line 1038, in save_hdf
    attrs._mnest_basename = self._mnest_basename
AttributeError: 'StarModel' object has no attribute '_mnest_basename'

[timothydmorton]

fixed on current master. thanks for the help!