Import rstudio api.
Closes #458
Merge branch 'master' into 466-github-api
Merge branch 'master' into 466-github-api
Revert "refactor: extract variable github_api_host"

This reverts commit e28acdfba847725be14c563c0610ecca485406c1.
Revert "refactor: extract method github_api_config"

This reverts commit e8ca8fd139c87cf83e1946d4be02b773c760122a.
Revert "Revert "refactor: extract method github_api_config""

This reverts commit e5748b0da2c68e13e4aa6c85b4d7c69d5369a40c.
Revert "Revert "refactor: extract variable github_api_host""

This reverts commit f8ac7d7a2386e5827e56191b2935a76ccd73aed5.
refactor: extract function github_api
allow installing the latest GitHub release by passing release = TRUE to, or using the syntax "user/repo@*" in install_github
update NEWS
supply test
Roxygenize
fix comment