fixes #7018: authors, not author, in composer

composer.json

@@ -3,7 +3,16 @@
   , "description": "Sleek, intuitive, and powerful front-end framework for faster and easier web development."
   , "keywords": ["bootstrap", "css"]
   , "homepage": "http://twitter.github.com/bootstrap/"
-  , "author": "Twitter Inc."
+  , "authors": [
+      {
+        "name": "Mark Otto",
+        "email": "markdotto@gmail.com",
+      },
+      {
+        "name": "Jacob Thornton",
+        "email": "jacobthornton@gmail.com",
+      }
+    ]
   , "license": "Apache-2.0"
 
 }