add readme.

Author: polidog

.scrutinizer.yml

@@ -0,0 +1,35 @@
+filter:
+    excluded_paths: [test/*]
+checks:
+    php:
+        code_rating: true
+        remove_extra_empty_lines: true
+        remove_php_closing_tag: true
+        remove_trailing_whitespace: true
+        fix_use_statements:
+            remove_unused: true
+            preserve_multiple: false
+            preserve_blanklines: true
+            order_alphabetically: true
+        fix_php_opening_tag: true
+        fix_linefeed: true
+        fix_line_ending: true
+        fix_identation_4spaces: true
+        fix_doc_comments: true
+tools:
+    external_code_coverage:
+        timeout: 600
+        runs: 2
+    php_analyzer: true
+    php_code_coverage: false
+    php_code_sniffer:
+        config:
+            standard: PSR2
+        filter:
+            paths: ['src']
+    php_loc:
+        enabled: true
+        excluded_dirs: [vendor, test]
+    php_cpd:
+        enabled: true
+        excluded_dirs: [vendor, test]

README.md

@@ -1,6 +1,7 @@
 # YConnect(Yahoo Japan) Provider for OAuth 2.0 Client
 
 [![Build Status](https://travis-ci.org/tavii/oauth2-yconnect.svg?branch=master)](https://travis-ci.org/tavii/oauth2-yconnect)
+[![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/tavii/oauth2-yconnect/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/tavii/oauth2-yconnect/?branch=master)
 
 This package provides YConnect(Yahoo Japan) OAuth2.0 support for the PHP League's [ OAuth 2.0 Client](https://github.com/thephpleague/oauth2-client).