Use solver_to_sumk and solver_to_sumk_block instead of previous maps
Remove all instances of map, map_inv, map_ind
Tidy up of unused functions in sumk_lda
Tidy up of trans_basis
Tidy up of symmetry

*changed map -> orb_map in symmetry to avoid using python keyword
Write shell equivalency information directly into h5 at conversion

* changed shellmap and invshellmap to corr_to_inequiv and inequiv_to_corr
* update_archive now calculates and stores these quantities for old archives
Tidy up of indices
Merge simple_point_dens_mat and density_gf into a single function density_matrix

density_matrix takes as argument method == using_gf or using_point_integration
More minor changes
Started work on lattice_gf