make "install" the default for --prefix, moritz++

Configure.pl

@@ -67,7 +67,7 @@
 $config{perl}   = $^X;
 $config{config} = join ' ', map { / / ? "\"$_\"" : $_ } @args;
 
-$config{prefix} = File::Spec->rel2abs($args{prefix} // '.');
+$config{prefix} = File::Spec->rel2abs($args{prefix} // 'install');
 
 # set options that take priority over all others
 my @keys = qw( cc ld make );