message: Fixed up grammar.md with rpc's and new scalar types.
diff: @@ -4,7 +4,7 @@ Grammar of the schema language {#flatbuffers_grammar}
  schema = include*
  ( namespace\_decl | type\_decl | enum\_decl | root\_decl |
  file_extension_decl | file_identifier_decl |
  - attribute\_decl | object )*
  + attribute\_decl | rpc\_decl | object )*
  include = `include` string\_constant `;`
  @@ -21,9 +21,15 @@ root\_decl = `root_type` ident `;`
  field\_decl = ident `:` type [ `=` scalar ] metadata `;`
  +rpc\_decl = `rpc_service` ident `{` rpc\_method+ `}`
  +
  +rpc\_method = ident `(` ident `)` `:` ident metadata `;`
  +
  type = `bool` | `byte` | `ubyte` | `short` | `ushort` | `int` | `uint` |
  -`float` | `long` | `ulong` | `double`
  - | `string` | `[` type `]` | ident
  +`float` | `long` | `ulong` | `double` |
  +`int8` | `uint8` | `int16` | `uint16` | `int32` | `uint32`| `int64` | `uint64` |
  +`float32` | `float64` |
  +`string` | `[` type `]` | ident
  enumval\_decl = ident [ `=` integer\_constant ]
  