Add freeintv

Author: ethanaobrien

cores.json

@@ -702,5 +702,17 @@
         },
         "license": "LICENSE",
         "repo": "https://github.com/EmulatorJS/dosbox-pure"
+    },
+    {
+        "name": "freeintv",
+        "extensions": [ "int", "rom", "bin" ],
+        "makeoptions": {
+            "buildpath": "./",
+            "makescript": "Makefile",
+            "arguments": []
+        },
+        "options": {},
+        "license": "LICENSE",
+        "repo": "https://github.com/EmulatorJS/FreeIntv"
     }
 ]