Added sanity check for search_pattern_parenthesised() in order not to invoke the parenthesised parser unless needed.  This fixes queries such as U(1).  Also, added printing of parenthesised parser output in the verbose mode.
Added sanity check for search_pattern_parenthesised() in order not to
invoke the parenthesised parser unless needed.  This fixes queries
such as U(1).  Also, added printing of parenthesised parser output in
the verbose mode.

tiborsimko/invenio-search,inveniosoftware/invenio-search,tiborsimko/invenio-search,tiborsimko/invenio-records,inveniosoftware/invenio-search,inveniosoftware/invenio-records,tiborsimko/invenio-records,inveniosoftware/invenio-records