Update README.md

Added links to contributing and the docs folder so Readme will be the go to starting point...for now.

Author: sphibbs

README.md

@@ -196,6 +196,8 @@ Be sure to check out the [Microsoft Azure Developer Forums on Stack Overflow](ht
 
 If you would like to become an active contributor to this project please follow the instructions provided in [Microsoft Azure Projects Contribution Guidelines](https://azure.github.io/guidelines/).
 
+More information about contributing to this repo can be found in [CONTRIBUTING md](https://github.com/Azure/azure-powershell/blob/preview/CONTRIBUTING.md) and the [Documentation](https://github.com/Azure/azure-powershell/tree/preview/documentation) folder.
+
 If you encounter any bugs with the library please file an issue in the [Issues](https://github.com/Azure/azure-powershell/issues) section of the project.
 
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