Revert "Hide dups in /tags/show_sentences_with_tag
Revert "Hide dups in /tags/show_sentences_with_tag

This reverts commit d48b1d25ed6c508ae69f619b2017b87190f73caa.

That commit introduced bug #1583: it messes up with the total
results counting query. GROUP BY is applied on a COUNT(*),
which makes it return as many rows as results and produces a
memory error.

Fix #1583.

Tatoeba/tatoeba2,Tatoeba/tatoeba2,Tatoeba/tatoeba2,Tatoeba/tatoeba2,Tatoeba/tatoeba2