Issue #22: Spacegroup db
Fix for issue #22 (closed) and correction of the spacegroup database.
Removed sublattice translations for all rhombohedral settings in the
space group database (setting 2 of space group 146, 148, 155, 160,
161, 166 and 167) in accordance International Tables.
The CIF reader is changed to (by default) assuming that all sublattice
translations are included in the symmetry operations listed in the CIF
file. With this, the cif file included in issue #22 should be read correctly.