Support repeated search string for collections.
Support repeated search string for collections.

Remove an "optimization" that would abort study search, if the search
string exactly matches the previous search. This would "kill" the search
feature if someone tried to find another study with, e.g., an author's
last name. Fixes #1029.

OpenTreeOfLife/opentree,OpenTreeOfLife/opentree,OpenTreeOfLife/opentree,OpenTreeOfLife/opentree,OpenTreeOfLife/opentree,OpenTreeOfLife/opentree