DOC: strings longer than min_itemsize are not truncated
Fixed docs on min_itemsize

Sorry, closed by mistake
 this is just a doc change, but you are wanting to change the error, no?
 No, my intention (here) was indeed just to update the docs.
(The other open PR related to `min_itemsize` has not much to do with this.)
 (I think the current behaviour is the sane one, don't you?!)
 ok why don't u update the doc string of append with an example as well then
 thanks!
