v1.21.0 log4net removed; custom HTTP headers
Bug fixes:
- #849 log4net dependency removed (via PR #890).
- #884 TokenResponse.Issued set to Now instead of UtcNow.
New features:
- #893 Add a convenience method to obtain a GoogleCredential from a JSON string.
- #913 Allow modification of HTTP requests for download and client requests.
Internal changes:
- #902 Split ResumableUpload class and introduced associated options.