Updated contributing guidelines

Author: SENya1990

CONTRIBUTING.md

@@ -1,4 +1,14 @@
+If you want to contribute a new diagnostic or feature to Acuminator, please first create an issue in the [GitHub repository](https://github.com/Acumatica/Acuminator/issues) describing the feature you want to add.
+This will allow us to discuss the implementation and ensure that it aligns with the project's goals. 
+
+**All new diagnostics must be approved by Acumatica before the implementation.** 
+
+For development guidelines, please refer to the following coding guidelines document:
 <a href="https://github.com/Acumatica/Acuminator/blob/dev/docs/dev/CodingGuidelines/CodingGuidelines.md">
    Coding Guidelines
 <a/>
-     
+
+For working with Git branches and commits please refer to the following Git guidelines document:
+<a href="https://github.com/Acumatica/Acuminator/blob/dev/docs/dev/CodingGuidelines/BranchAndCommitGuidelines.md">
+   Guidelines for working with Git branches and commits
+<a/>