parentheses > commas (#1308)

* Update 01.md

A few small changes that can potentially help a broader audience (non-developers) follow the meaning.

* monospace hex

Co-authored-by: Asai Toshiya <to.asai.60@gmail.com>

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Co-authored-by: fiatjaf_ <fiatjaf@gmail.com>
Co-authored-by: Asai Toshiya <to.asai.60@gmail.com>

01.md

@@ -43,16 +43,16 @@ To obtain the `event.id`, we `sha256` the serialized event. The serialization is
 ```
 
 To prevent implementation differences from creating a different event ID for the same event, the following rules MUST be followed while serializing:
-- Whitespace, line breaks or other unnecessary formatting should not be included in the output JSON.
-- No characters except the following should be escaped, and instead should be included verbatim:
-  - A line break, `0x0A`, as `\n`
-  - A double quote, `0x22`, as `\"`
-  - A backslash, `0x5C`, as `\\`
-  - A carriage return, `0x0D`, as `\r`
-  - A tab character, `0x09`, as `\t`
-  - A backspace, `0x08`, as `\b`
-  - A form feed, `0x0C`, as `\f`
 - UTF-8 should be used for encoding.
+- Whitespace, line breaks or other unnecessary formatting should not be included in the output JSON.
+- The following characters in the content field must be escaped as shown, and all other characters must be included verbatim:
+  - A line break (`0x0A`), use `\n`
+  - A double quote (`0x22`), use `\"`
+  - A backslash (`0x5C`), use `\\`
+  - A carriage return (`0x0D`), use `\r`
+  - A tab character (`0x09`), use `\t`
+  - A backspace, (`0x08`), use `\b`
+  - A form feed, (`0x0C`), use `\f`
 
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