Merge pull request #1071 from stan-dev/v0.9-release

Prepare items for v0.9.0 release

Merge pull request #989 from stan-dev/v0.8.1-bugfix-rel

Prepare v0.8.1 bugfix release

Prepare v0.8.0 release (#974)

* Prepare for v0.8.0 release

* Cherry-pick fix for Onedrive path issues

Merge pull request #893 from stan-dev/v0.7.1-release

Prepare v0.7.1 bugfix-release

Merge pull request #885 from stan-dev/website-v0.7.0

Website v0.7.0

Merge pull request #834 from stan-dev/diagnose-method-duplicate-stdout

change duplicate stdout_file to stderr_file

Merge pull request #794 from stan-dev/next-release

cmdstanr v0.6.0

Merge pull request #678 from stan-dev/bump-to-0.5.3

Bump version to 0.5.3

Update NEWS.md

update website (home and news pages for 0.5.1)