Added split API
Updated README to reference splits
Ordered alphabetically the full list of fields
Merge pull request #20 from pochocosta/Ordered-alphabetically-the-full-list-of-fields

Ordered alphabetically the full list of fields
Merge pull request #18 from fengb/splits

Splits
Split tests up for easier debugging
Optional start_date / end_date
Updated README to reflect new API call
Folded start_date/end_date into options per @herval
Merge pull request #17 from fengb/optional-historical-dates

Optional historical dates
Merge branch 'master' of github.com:herval/yahoo-finance into single-quotes

Conflicts:
	lib/yahoo_finance.rb
	test/yahoo_finance_test.rb