py-empyrical: updated to 0.5.0

0.5.0
DEP: Deprecate all data reading functionality via pandas-datareader
* DEP: Deprecate all functions using pandas-datareader
* DOC: Update README with deprecation documentation
* STY: Markdown style
* STY: Markdown style again
* REV: revert previous commit
* STY: typo
* STY: consistent naming convention
* DEP: also deprecate any cacheing of data
* DEP: forgot to deprecate additional funcs
* REV: get_utc_timestamp should not be deprecated
* ENH: add function to compute returns from prices
* BUG: wrap import in try-except
* MAINT: update deprecation warning
* MAINT: move `simple_returns` func to `stats` module
* MAINT: don't raise deprecation warning for _1_bday_ago
* DOC: remove suggestions
* TST: added test for simple_returns
* MAINT: add simple_returns to init
* TST: fixed simple_returns test
* STY: use size, not shape
* TST: tests passing
* DOC: 1_bday_ago no longer deprecated

(adam)