Log Message:
hub: Update to 2.9.0

Changes:
2.9.0
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Features
 - Add support for hub ci-status --format <FORMAT> string
 - Add hub create --remote-name <REMOTE> flag
 - Allow passing in a raw request body via hub api --input <FILE>
 - Cache HTTP 4xx (except 403) server responses in hub api --cache

Fixes
 - Ensure consistent ordering of hub ci-status -v results
 - Avoid crashing on invalid GitHub hostname
 - Fix parsing empty string within command-line arguments

2.8.4
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 - Add hub api -H flag to set HTTP request headers
 - Add hub api -i flag to output HTTP response headers
 - Change how hub api deals with HTTP errors:
    - HTTP response is now printed on stdout regardless of HTTP status
    - No longer print an extra newline after HTTP response body
    - No more Error: HTTP {STATUS} message on stderr
    - hub exits with status 22 instead of 1
 - Fix hub execution under WSL (Windows Subsystem for Linux)