dumplog fixes: genocide list, survivor's tombstone

dumplog fixes: genocide list, survivor's tombstone

The dumplog data was including a final tombstone unconditionally,
which looked awfully strange for characters who didn't die.  Make
it conditional, like actual end-of-game tombstone.  (One difference
though:  dumplog has a tombstone for hero who died from genocide,
end-of-game does not.  I think the latter should display one even
though no grave gets generated.)  [Potential for future enhancement:
add some alternate ascii art in place of tombstone for survivors.]

The list of genocided and/or extincted species was never shown
since caller passed 'a' to list_genocided() and it expected 'y'.
Also, once shown, the list entries were lacking indentation that
other sections of the dump generally have.

Both vanquished monsters and genocided/extinct monsters included
a blank line separator even when there was no feedback, making a
noticeable gap in the dumplog text.  Have them report "no creatures
vanquished" and "no species genocided", when applicable, so that
their separator lines always have something to separate.

When dumping, omit a couple of blank lines each from vanquished
creatures list, genocided species list, and tombstone so the
relevant sections of the dump are more compact.