Implemented package imports

tests/programs/jump-near.q

@@ -1,3 +1,5 @@
+import sys
+
 main() {
 	x := 10
 
@@ -175,13 +177,13 @@ main() {
 		fail()
 	}
 
-	exit(0)
+	success()
 }
 
 fail() {
-	exit(1)
+	sys.exit(1)
 }
 
-exit(code) {
-	syscall(60, code)
+success() {
+	sys.exit(0)
 }