DOC: improve documentation 2

Refs: #26

CONTRIBUTING.md

-# Contributing
+# Contributing
 
 First off, thanks for taking the time to contribute!
 
-## How Can I Contribute?
+## How Can I Contribute?
 
 - Reporting bugs
 - Suggesting enhancements
 - Code contribution
 
-## Styleguides
+## Styleguides
 
 - [Git Commit message](documentation/30_Contributor_doc/GIT_CONVENTION.md)
 

README.md

@@ -8,10 +8,10 @@ Comptoir du Libre v3+ (Symfony)
 
 ## Documentation
 
+- [QA : URLs + online tools](documentation/QA-tools.md)
 - [Install documentation](documentation/10_Install_doc/)
 - [Developer documentation](documentation/30_Contributor_doc/)
-- [QA : URL + online tools](documentation/QA-tools.md)
-
+- [Mementos](documentation/90_Mementos/)
 
 ## License
 

documentation/README.md

 # Documentation
 
+- [QA : URL + online tools](QA-tools.md)
 - [Install documentation](10_Install_doc/)
 - [Developer documentation](30_Contributor_doc/)
-- [QA : URL + online tools](QA-tools.md)
+- [Mementos](documentation/90_Mementos/)