Merge pull request #4 from Tpt/composer

Add composer.json.

composer.json

@@ -0,0 +1,29 @@
+{
+  "name": "digitalbazaar/json-ld",
+  "type": "library",
+  "description": "A JSON-LD Processor and API implementation in PHP.",
+  "keywords": [
+    "JSON",
+    "Linked Data",
+    "JSON-LD",
+    "RDF",
+    "Semantic Web",
+    "jsonld"
+  ],
+  "homepage": "https://github.com/digitalbazaar/php-json-ld",
+  "license": "BSD-3-Clause",
+  "authors": [
+    {
+      "name": "Digital Bazaar, Inc.",
+      "email": "support@digitalbazaar.com",
+      "url": "http://digitalbazaar.com/"
+    }
+  ],
+  "require": {
+    "php": ">=5.3.0",
+    "ext-json": "*"
+  },
+  "autoload": {
+    "files": [ "jsonld.php" ]
+  }
+}