hush: audit and fix "interactive shell" setup code.

function                                             old     new   delta
block_signals                                          -     139    +139
maybe_set_to_sigexit                                   -      47     +47
run_list                                            2018    2030     +12
expand_variables                                    2155    2165     +10
maybe_set_sighandler                                  47       -     -47
hush_main                                            992     918     -74
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(add/remove: 2/1 grow/shrink: 2/1 up/down: 208/-121)           Total: 87 bytes

1 file changed