add valid licenses to schema, pass validation

fonts-schema.json

@@ -24,7 +24,16 @@
                     "type":"string",
                     "format":"uri"
                 },
-                "license": { "type":"string" },
+                "license": {
+                    "type":"string",
+                    "enum": [
+                        "Apache",
+                        "GNU GPL",
+                        "MIT",
+                        "public domain",
+                        "SIL OFL"
+                    ]
+                },
                 "ligatures": { "type":"boolean" },
                 "style": {
                     "type":"string",

fonts.json

@@ -245,6 +245,7 @@
     },
     "daddytimemono": {
         "author": "Jason Stewart",
+        "license": "SIL OFL",
         "ligatures": false,
         "name": "DaddyTimeMono",
         "rendering": "vector",
@@ -558,7 +559,7 @@
     "luculent": {
         "author": "Andrew Kensler",
         "description": "Luculent is a narrow typeface with full bold, italic versions, each covering 643 characters. All glyphs are distinct and full of character. Additionally, the italics bring a wonderful twist to what is already an outstanding and unique font.",
-        "license": "SIl OFL",
+        "license": "SIL OFL",
         "ligatures": false,
         "name": "Luculent",
         "rendering": "vector",