remove aoc solutions

examples/euler/euler_09.zr

@@ -0,0 +1,7 @@
+func main[] : i64
+    for a in 1..1000
+        for b in 1..1000
+            c := 1000 - b - a
+            if a * a + b * b == c * c
+                io.println_i64(a * b * c)
+                return 0