Treat unstemmed words as normal search terms.

has_normal_search_terms? was only returning true if the query had a
stemmed search term in it, such as Zterm. Searching for a word with
capital letters, such as NHS, translates to an unstemmed query term
“nhs”. This would not match and the search would default to sorting
by newest rather than relevance. Unstemmed query terms should still
match as a normal search term, not a prefixed one.

lib/acts_as_xapian/acts_as_xapian.rb

@@ -411,10 +411,9 @@ def has_normal_search_terms?
       #x = ''
       query.terms.each do |t|
         term = t.term
-        #x = x + term.to_yaml + term.size.to_s + term[0..0] + "*"
-        if term.size >= 2 && term[0..0] == 'Z'
-          # normal terms begin Z (for stemmed), then have no capital letter prefix
-          ret = true if term[1..1] == term[1..1].downcase
+        # normal terms begin Z (for stemmed), or have no capital letter prefix
+        if term.size >= 1 && (term[0..0] == 'Z' || term[0..0] == term[0..0].downcase)
+          ret = true
         end
       end
       ret