docs&specs. _h.asssoc, _h.delete, _h.each_key
Reorganize hash spec
_h.each_key: add the correct result to the example
Merge pull request #22 from jastix/hash

docs&specs. _h.asssoc, _h.delete, _h.each_key
docs&specs. _h.each_value, _h.empty, _h.fetch
Merge pull request #23 from jastix/hash

docs&specs. _h.each_value, _h.empty, _h.fetch
docs&specs: _h.flatten, _h.get, _h.has_value
docs&specs: _h.has_key, _h.keep_if, _h.key
Merge pull request #24 from jastix/hash

docs&specs: _h.flatten, _h.get, _h.has_value
fix _a.min, _a.max bug. Closes #25
Merge branch 'master' of github.com:rubyjs/core-lib
Fix _a.shuffle. Closes #26