Add contribution guide (#55)

Author: bryanbcook

CONTRIBUTING.md

@@ -0,0 +1,62 @@
+# Contribution Guide
+
+## Environment Setup
+
+### Tools
+
+Local development requires the following:
+
+- PowerShell 7.x
+- Pester 5.7.1
+- [Pandoc](https://pandoc.org)
+- Visual Studio Code, with the following extensions:
+  - Test Adapter Converter
+  - Test Explorer UI
+  - Pester Tests
+
+Development is presently done on Windows 11, though conceptually it should work on Linux
+
+### Codespace
+
+As an alternative to local development environments, a GitHub Codespace can be used to build and test. Codespace usage has an [associated cost](https://docs.github.com/en/billing/concepts/product-billing/github-codespaces). The free option should be sufficient for most developers.
+
+Codespaces are Linux based and require the above tools to be installed.
+
+TODO: DevContainer configuration with tools installed is pending.
+
+### Google Application
+
+The environment uses a Google Application with the following setup. The published module has credentials defined, but if you may want to create an application for local testing purposes.
+
+While this is not a fully documented walk-through on how to create a Google Application in the [Developer Console](https://console.cloud.google.com), the application has the following details.
+
+- Branding:
+  - An app name + support email
+- Audience: Testing
+- Clients:
+  - Web Application
+  - Authorized redirect URIs:
+    - <http://localhost/oauth2callback>
+    - <https://localhost:8040/oauth2callback>
+- Data Access: uses the following scopes:
+
+- <https://www.googleapis.com/auth/blogger>: manage blogger account and posts
+- <https://www.googleapis.com/auth.drive.file>: upload and manage files into Google Drive that are scoped to the application.
+
+For local testing, you'll need the Client ID and Client Secret
+
+## Running Locally
+
+Within Visual Studio Code, you should be able to run the tests with no additional configuration.
+
+To test the module manually, you will need to provide your client-id and client-secret as environment variables.
+
+```shell
+cd ./src
+./reload.ps1 # to load the source into memory
+
+$env:PSBLOGGER_CLIENT_ID = "<your-id>"
+$env:PSBLOGGER_CLIENT_SECRET = "<your-secret>"
+
+Initialize-Blogger
+```