update version to 0.49.0

Bump again

Bump rc

Merge pull request alpacahq#191 from alpacahq/rc4

Fix exception handling, timestamp precisions

Tag 0.47rc3

Update RC version

Update version to 0.47rc1

Fixes:

  - Update timestamp format of portfolio history dataframe to match new API sepecification

Features:

  - Add support for equity history endpoint
  - Add daily open/close Polygon endpoint

Fixes:

  - Add missing declaration of alpha_vantage package