Adding len() builtin and TYPE_SLICE

main.kl

@@ -1,8 +1,16 @@
 #import "base.kl"
 
+test_arrays :: ()
+  array := [4]int{1,2,3,4}
+  item  := array[0]
+  length := len(array)
+  slice: []int = array
+  slice_length := len(slice)
+
 main :: (argc: int, argv: **char): int
   memory := reserve(size = 10000)
   handle := Windows.GetStdHandle(Windows.STD_OUTPUT_HANDLE)
 
+
   string: *char = "hello world"
   Windows.WriteConsoleA(handle, string->*void, 11, 0, 0)