Add basic smd file syntax highlighting

Author: StefanH-AT

package.json

@@ -196,6 +196,16 @@
                     "npc_sounds_*.txt",
                     "level_sounds_*.txt"
                 ]
+            },
+            {
+                "id": "smd",
+                "aliases": [
+                    "Valve SMD",
+                    "Source SMD"
+                ],
+                "extensions": [
+                    ".smd"
+                ]
             }
         ],
         "grammars": [
@@ -243,6 +253,11 @@
                 "language": "rad",
                 "scopeName": "source.rad",
                 "path": "./syntaxes/rad.tmLanguage.json"
+            },
+            {
+                "language": "smd",
+                "scopeName": "source.smd",
+                "path": "./syntaxes/smd.tmLanguage.json"
             }
         ],
         "commands": [

syntaxes/smd.tmLanguage.json

@@ -0,0 +1,28 @@
+{
+	"$schema": "https://raw.githubusercontent.com/martinring/tmlanguage/master/tmlanguage.json",
+	"name": "SMD",
+	"scopeName": "source.smd",
+	"patterns": [
+        {
+            "include": "source.kv#comment"
+        },
+        {
+            "include": "source.kv#number"
+        },
+        {
+            "include": "#keywords"
+        },
+        {
+            "include": "source.kv#stringUnquoted"
+        },
+        {
+            "include": "source.kv#stringQuoted"
+        }
+	],
+	"repository": {
+		"keywords": {
+            "match": "(version|nodes|end|triangles|skeleton|time)",
+            "name": "keyword.smd"
+        }
+	}
+}