Merge pull request #69 from OpenZeppelin/update-error-codes-stellar

update the error codes after the refactor

Author: ozgunozerk

content/stellar-contracts/index.mdx

@@ -30,19 +30,24 @@ we use the following convention:
 
 * Fungible: `1XX`
 * Non-Fungible: `2XX`
+* RWA: `3XX`
+* Vault: `4XX`
 
-Any future tokens will continue from `4XX`, `5XX`, and so on.
+Any future tokens will continue from `5XX`, `6XX`, and so on.
+
+Similarly, utilities and other modules have their own error codes:
 
 * Utilities: `1XXX`
   * Pausable: `10XX`
   * Upgradeable: `11XX`
-  * Access: `12XX`
-    * Role Transfer (internal common module for 2-step role transfer): `120X`
-    * Access Control: `121X`
-    * Ownable: `122X`
   * Merkle Distributor: `13XX`
-
-Any future utilities will continue from `14XX`, `15XX`, and so on.
+  * Crypto: `14XX`
+  * Math: `15XX`
+* Access: `2XXX`
+  * Access Control: `20XX`
+  * Ownable: `21XX`
+  * Role Transfer (internal common module for 2-step role transfer): `22XX`
+* Accounts: `3XXX`
 
 ## Important Notes
 As a deliberate design choice, this library manages the TTL for temporary and persistent storage items.