static detach/reattach: options with append semantics are appended to on subsequent reattaches

Created by: Carrotman42

For example, when -client_lib (a liststring_t) is specified in two consecutive attach/detach runs, the second attach will simply append its value for -client_lib to the value in the first run instead of overwriting it.

I'm thinking that we should just set the dynamo_options back to default values before each time the options are parsed.