3.4.0

• Major efficiency updates:
  • Uses _scan_sm_stol_till_match and turbo-charged StructureMatcher methods from doped
v3, speeding up structure matching (e.g. in snb-regenerate for identifying distinct defect
    geometries) by >~3 orders of magnitude.
  • Uses caching in atomic displacement calculations (for "disp"/"max_dist" metrics)
  • Use efficient Voronoi analyzer from doped v3 for multiplicity determination.
  • More efficient (and cleaner) plotting with many defects/distortions
• Add Dimer to default distortions grid output for vacancies, following discussions and testing for
  cation vacancies in oxides.
• Miscellaneous:
  • All snb-xxx functions now auto-detect if running within a defect folder or in a top-level
    directory (i.e. auto --all behaviour).
  • Handling of gzipped OUTCAR.gz files for energy parsing.
  • For (rare) cases of degenerate choices of NNs to distort in terms of distance, but non-degenerate
    combinations (e.g. distorting 2 NNs of a square coordination, could be cis or trans choices),
    the choice is made deterministically; choosing the combination with the shortest distances between
    distorted NNs (i.e. the cis choice).
  • Greater verbosity control
  • Some code cleanup and formatting, and robustness updates