Use Erlang string case folding. Add word mappings to normalize

priv/normalize-words-mapping.csv

@@ -0,0 +1,25 @@
+# This is a list of mappings used by z_string:normalize/1
+# It maps various spellings of common words (like city names) to a canonical form.
+
+kiev, kyiv
+kiyev, kyiv
+київ, kyiv
+киев, kyiv
+
+odessa, odesa
+одеса, odesa
+одесса, odesa
+אָדעס, odesa
+οδησσόσ, odesa
+
+kharkov, kharkiv
+харків, kharkiv
+харьков, kharkiv
+
+lwiw, lviv
+lwów, lviv
+львів, lviv
+львов, lviv
+львоў, lviv
+ilyvó, lviv
+לעמבעריק, lviv

src/z_mochinum.erl

@@ -324,7 +324,7 @@ digits_test() ->
 
 frexp_test() ->
     %% zero
-    ?assertEqual({0.0, 0}, frexp(0.0)),
+    ?assertEqual({+0.0, 0}, frexp(+0.0)),
     %% one
     ?assertEqual({0.5, 1}, frexp(1.0)),
     %% negative one