Update README.md

Update regex solution to string compression.

Update string compression first solution. (Goldman Sachs asked on interview.) Add solution to eight queens.

Working on eight queens problem.

Add 4th solution to ways to make change.

Update Bottom Up staircase solution.

Add find duplicate value in array solution to misc.

Add leetcode problem #113 tree paths sum to misc.

Update reverse number in misc to handle negative numbers.

Add counting sort to misc/sorting. Add Fisher-Yates / Knuth Shuffle to misc.

Add second less efficient solution to generate parens.

Add sudoku solver to misc.

Add sudoku validator to misc.

Add sieve primes solution to misc.

Update