Update to TypeScript 2.6

fixes #5

Author: jason0x43

package-lock.json

@@ -20,7 +20,7 @@
     "shelljs": "~0.7.8",
     "tslint": "~5.7.0",
     "typedoc": "~0.8.0",
-    "typescript": "~2.5.2"
+    "typescript": "~2.6.1"
   },
   "devDependencies": {
     "@types/chalk": "~0.4.31",
@@ -58,4 +58,4 @@
       ]
     }
   }
-}
+}

package.json

@@ -14,9 +14,9 @@ getConfigs()
 		return outDir;
 	})
 	.filter(outDir => Boolean(outDir))
-	.reduce((outDirs: string[], dir: string) => {
-		if (outDirs.indexOf(dir) === -1) {
-			return [ ...outDirs, dir ];
+	.reduce((outDirs: string[], dir: string | undefined) => {
+		if (dir && outDirs.indexOf(dir) === -1) {
+			return [...outDirs, dir];
 		}
 		return outDirs;
 	}, [])