Update ICU to 58.3

- This adds the new Japanese ascension era (Reiwa)
- This updates timezone data to 2019a
- Updated script for git instead of SVN
- Regenerated locale data

intl/icu/source/i18n/zonemeta.cpp

@@ -683,7 +683,6 @@ ZoneMeta::createMetazoneMappings(const UnicodeString &tzid) {
                     mzMappings = new UVector(deleteOlsonToMetaMappingEntry, NULL, status);
                     if (U_FAILURE(status)) {
                         delete mzMappings;
-                        deleteOlsonToMetaMappingEntry(entry);
                         uprv_free(entry);
                         break;
                     }