Add benchark for compile-keymap Implement `tasty-bench` method: 1. Set n = 1. 2. Measure execution time t_n of n iterations and execution time t_2n of 2n iterations. 3. Find t which minimizes deviation of (n·t, 2·n·t) from (t_n, t_2n), namely t = (t_n + 2·t_2n)/5n. 4. If deviation is small enough (see --stdev CLI parameter), return t as a mean execution time. 5. Otherwise set n = 2·n and jump back to Step 2. See: https://hackage.haskell.org/package/tasty-bench