Add code maturity

Author: montyly

README.md

@@ -9,6 +9,7 @@ We welcome contributions, and you can contribute by following our [contributing
 **Table of contents:**
 
 - [Development guidelines](./development-guidelines)
+  - [Code Maturity](./development-guidelines/code_maturity.md): Criteria for developers and security engineers to use when evaluating a codebase’s maturity
   - [High-level best practices](./development-guidelines/guidelines.md): High-level best-practices for all smart contracts
   - [Incident Response Recommendations](./development-guidelines/incident_response.md): Guidelines on how to formulate an incident response plan
   - [Secure development workflow](./development-guidelines/workflow.md): A rough, high-level process to follow while you write code

SUMMARY.md

@@ -3,6 +3,7 @@
 [Introduction](./README.md)
 
 - [Development-guidelines](./development-guidelines/README.md)
+  - [Code Maturity](./development-guidelines/code_maturity.md)
   - [High-level best practices](./development-guidelines/guidelines.md)
   - [Token integration checklist](./development-guidelines/token_integration.md)
   - [Incident Response Recommendations](./development-guidelines/incident_response.md)

development-guidelines/README.md

@@ -1,5 +1,6 @@
 List of smart contract development best practices
 
+- [Code Maturity](./code_maturity.md): Criteria for developers and security engineers to use when evaluating a codebase’s maturity
 - [High-level best practices](./guidelines.md): High-level best-practices for all smart contracts
 - [Token integration checklist](./token_integration.md): What to check when interacting with arbitrary tokens
 - [Incident Response Recommendations](./incident_response.md): Guidelines on how to formulate an incident response plan