Enh: Implements signals and alarm()

[snoopyjc]

Enhancement: Implements signals and alarm() and also anonymous sub's. Sample perl code:

$SIG{ALRM} = sub { die "timeout"; };
eval {
    alarm($TIME);
    ...
    alarm(0);
};
if($@ =~ /timeout/) {
    ...
}

[snoopyjc]

Fixed in https://github.com/snoopyjc/pythonizer