Initial configuration documentation.

Author: tomzx

docs/02-Configuration.md

@@ -0,0 +1,34 @@
+# Configuration
+
+You may configure various options within `php-semver-checker` to make them more to your liking. In order to do so, you have to create a JSON file which will be passed to `php-semver-checker` using the `--config myconfig.json` or `-c myconfig.json` flag.
+
+```json
+{
+	"level": {
+		"mapping": {
+			"V001": "PATCH"
+		}
+	}
+}
+```
+
+## Configuration sections
+
+The following describes every section of the configuration in more details in order to allow you to customize `php-semver-checker` to your liking.
+
+### Level
+
+#### Mapping
+
+Every item in the mapping section presents a rule that you may override. The key is the ruleset code and the value is the semantic version level you want the rule to generate when it is detected.
+
+```json
+{
+	"level": {
+		"mapping": {
+			"V001": "PATCH",
+			"V006": "MAJOR",
+		}
+	}
+}
+```