THRIFT-299. doc: binary type isn't documented nor demonstrated in the tutorial

The existence of the "binary" type is now documented in the relevant places. 

git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@739702 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/doc/thrift.bnf b/doc/thrift.bnf
index 60e757d..d16ec05 100644
--- a/doc/thrift.bnf
+++ b/doc/thrift.bnf
@@ -48,11 +48,11 @@
     <field-name> ::= STRING
 
     <field-type> ::= T_BOOL | T_BYTE | T_I8 | T_I16 | T_I32 | T_I64 | T_DOUBLE
-                     | T_STRING | T_STRUCT | T_MAP | T_SET | T_LIST
+                     | T_STRING | T_BINARY | T_STRUCT | T_MAP | T_SET | T_LIST
 
       <field-id> ::= I16
 
-    <field-data> ::= I8 | I16 | I32 | I64 | DOUBLE | STRING |
+    <field-data> ::= I8 | I16 | I32 | I64 | DOUBLE | STRING | BINARY
                      <struct> | <map> | <list> | <set>
 
            <map> ::= <map-begin> <field-datum>* <map-end>