Add documentation for db_path config

Closes #6

README.md

@@ -6,3 +6,33 @@
 ```
 go install git.nagee.dev/isthisnagee/diary@v0.0.1
 ```
+
+
+## Configuration
+
+### Valid locations for the config file
+
+
+The config file can be passed to the `diary` command through a command line
+arg. For example: `diary --config=~/.diary.toml`
+
+When there is no config argument, `diary` looks for the config here:
+
+- `$HOME/.config/diary/diary.toml`
+
+
+### Configuration options
+
+
+#### `db_path`
+
+- Name: `db_path`
+- Type: String
+- Default: `~/.diary.sql`
+- Description: The location of the sqlite database. If the file does not exist,
+  it will be created.
+
+```
+db_path = "path/to/wherever/you/want/the/db/file"
+```
+