high-level routines for SOC; bandstructure, PDOS, local bandgap for G0W0/SOC

[JWilhelm]

• SOC routines from Hartwigsen pseudopotentials in

soc_pseudopotential_methods.F
soc_pseudopotential_utils.F

(for building SOC potential matrix in spinor format)

• post-SCF bandstructure code: bandstructure, DOS, PDOS, local bandgap, local valence band maximum, local conduction band minimum for DFT, DFT+SOC, G0W0, G0W0+SOC

[JWilhelm]

Thanks for triggering the psmp regtest, Ole!