add basics of if statement emitting

- add util mkLLVMBool
 - add left/right paren to if statements
 - lowkey fix for statements' semicolon

examples/hello.ry

@@ -1,5 +1,14 @@
 // import std;
 
+fn multwo(num: i32, double_flag: bool) i32 {
+    // TODO resolve expr variables
+    if (true) {
+        return 1 * 2;
+    } else {
+        return 1;
+    }
+}
+
 fn add(a: i32, b: i32) i32 {
     return 69 + 69;
 }