[ci skip] Add new global MBString constants to UPGRADING

The constants are mentioned further up in the New Features section,
but weren't explicitly listed under the New Global Constants section.

diff --git a/UPGRADING b/UPGRADING
index 0db37b27e751a1549c382412d7bda0da4dc5e5a4..db01dc0064eb13d940689df2e048a98d568024e1 100644 (file)
--- a/UPGRADING
+++ b/UPGRADING
@@ -432,6 +432,13 @@ Curl:
 JSON:
   . JSON_THROW_ON_ERROR
 
+MBString:
+  . MB_CASE_FOLD
+  . MB_CASE_LOWER_SIMPLE
+  . MB_CASE_UPPER_SIMPLE
+  . MB_CASE_TITLE_SIMPLE
+  . MB_CASE_FOLD_SIMPLE
+
 PGSQL:
   . Requires Postgres 9.3
     - PGSQL_DIAG_SCHEMA_NAME