Update docs to include an migration guide and changes

Author: No767

docs/dev-guide/index.rst

@@ -10,3 +10,4 @@ Rodhaj offers a developer guide so future developers can easily get started with
    intro
    contributing
    faq
+   migrating-to-yaml

docs/dev-guide/intro.rst

@@ -53,11 +53,11 @@ Setup
     poetry install \
     && poetry run pre-commit install
 
-3. Copy over the ``.env`` template over to the ``bot`` directory. Modify the values as appropriate.
+3. Copy over the ``config-example.yml`` template over to the ``bot`` directory. Modify the values as appropriate.
 
 .. code-block:: bash
 
-    cp envs/dev.env bot/.env
+    cp config-example.yml bot/config.yml
 
 4. Run the SQL migrations
 

docs/dev-guide/migrating-to-yaml.rst

@@ -0,0 +1,59 @@
+=================
+Migrating to YAML
+=================
+
+Rodhaj now uses an new config format, YAML.
+Previously, the project utilized an ENV file for configuration, but
+due to issues such as the inability for better structured data and others,
+the project has migrated to YAML.
+
+The details of the motivation can be found in
+`PR #59 <https://github.com/transprogrammer/rodhaj/pull/59>`_.
+
+.. note::
+
+    - ``*.yaml`` files are ignored and not read by the config loader. Ensure that your YAML file uses the ``*.yml`` file extension.
+    - The config file is stored in the same location as the ``.env`` file. It will always be read under ``bot/config.yml``.
+    
+Changes
+=======
+
+Grouped entries
+---------------
+
+The bot token, and others are merged into one mapping. This mapping key is denoted
+by ``rodhaj``. Any and all configuration options in relation to the bot can be found
+under that mapping.
+
+To illustrate, an example comparison of the old and new config format is shown below:
+
+``.env``
+
+.. code-block:: bash
+
+    TOKEN=...
+    DEV_MODE=False
+
+``config.yml``
+
+.. code-block:: yaml
+
+    rodhaj:
+        token: ...
+        dev_mode: False # This key-value pair can also be removed to disable the dev mode feature
+
+Rodhaj's Guild ID can now be set via the config
+-----------------------------------------------
+
+Instead of hardcoding the Guild ID into the code, to allow for flexibity in development,
+the Guild ID can now be set via the config. This is acheived through the ``guild_id`` entry as illustrated.
+
+.. code-block:: yaml
+
+    rodhaj:
+        guild_id: 1234567890 # This ID is the guild that is associated with Rodhaj for operations
+
+PostgreSQL Connection URI
+-------------------------
+
+The PostgreSQL URI is mostly the same, but is now under the ``postgres_uri`` entry.