healpix: add lex->ring
healpix: add ring_decompose
healpix: add ring_compose
willman
temp mess
healpix: ring_to_lex, still messy
cleaner
healpix: add nested index
healpix: make interface more sane.
misc healpix-related fixes
healpix fix
hpgrid: clean up, add mode options
add new simpler hitlist
hitlist: separate adding and agreement-finding
blind: switch to new hitlist
blind: cleanup
blind: remove multi-threading
add handlehits; make blind use it.
rearrange agreeable
remove hitlist_healpix