[ready?] Fish trap

I don't know how this trap is called in English. In childhood we used this for fishing.

small examples:
http://www.instructables.com/id/Fish-Bottle-Trap/
http://www.nano-reef.com/topic/249712-water-bottle-fish-trap/
http://offgridsurvival.com/fishing-trap/

it this PR i mean big version of fish trap. Make it from plastic bottles and canisters, reload with bait and place in water, go away and return in half an hour, get the fish or several.


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This trap increases the diversity of survival in the wild.
Ok, my mistake: I thinking that `sees()` mean "real can see". 

May be I can use here `rl_dist() < 10` or something like that? 

>presumably underwater

yes...really. But usually it will be in shallow water, that not deep and transparent. For me it is important to leave a message that there is some catch, so somehow illogical to miss message when no catch.

ok?