Add redirectors for SQL routine change

docs/src/main/sphinx/redirects.txt

@@ -10,3 +10,18 @@ connector/atop.md connector/removed.md
 connector/localfile.md connector/removed.md
 connector/accumulo.md connector/removed.md
 security/apache-ranger-access-control.md security/ranger-access-control.md
+routines.md udf.md
+routines/function.md udf/function.md
+routines/introduction.md udf/introduction.md
+routines/begin.md udf/sql/begin.md
+routines/case.md udf/sql/case.md
+routines/declare.md udf/sql/declare.md
+routines/examples.md udf/sql/examples.md
+routines/if.md udf/sql/if.md
+routines/iterate.md udf/sql/iterate.md
+routines/leave.md udf/sql/leave.md
+routines/loop.md udf/sql/loop.md
+routines/repeat.md udf/sql/repeat.md
+routines/return.md udf/sql/return.md
+routines/set.md udf/sql/set.md
+routines/while.md udf/sql/while.md