binary expressions are working fully now

tests/file.stlg

@@ -1,3 +1,14 @@
-export fn doThings() {
-    power.myPowerItem(12.45 + 5);
+fn myPowerItem(arg) {
+    
 }
+
+fn doThings(x, y, z) {
+    let item = myPowerItem((12.45 + 5 * 123) ** 2);
+
+    let item2 = 5 + 2 - 5 + 123.24323 / 234 ** 21 - (15 / 2);
+}
+
+
+fn main() {
+    doThings(1, 2, 3)
+}