enabled TS strict mode

tsconfig.json

@@ -12,10 +12,10 @@
     "baseUrl": "./",
     "incremental": true,
     "skipLibCheck": true,
-    "strictNullChecks": false,
+    "strict": true,
-    "noImplicitAny": false,
+    "noImplicitAny": true,
-    "strictBindCallApply": false,
+    "strictBindCallApply": true,
-    "forceConsistentCasingInFileNames": false,
+    "forceConsistentCasingInFileNames": true,
-    "noFallthroughCasesInSwitch": false
+    "noFallthroughCasesInSwitch": true
   }
 }