- fix conflict between ternary operator and postfix existential operator

- add null coalescing operators
- add `for let`, `extern|require`, `require|extern` statements

Author: daiyam

package.json

@@ -26,7 +26,7 @@
 		"src"
 	],
 	"dependencies": {
-		"@kaoscript/ast": "0.1.x"
+		"@kaoscript/ast": "0.2.x"
 	},
 	"devDependencies": {
 		"chai": "2.x",