Merge branch 'develop' of https://github.com/stan-dev/stan into develop
Merge branch 'develop' of https://github.com/stan-dev/stan into develop
Merge branch 'develop' of https://github.com/stan-dev/stan into develop
Merge branch 'develop' of https://github.com/stan-dev/stan into develop
fixed dump to accept zero-length arrays and vectors
Merge pull request #832 from stan-dev/feature/issue-683-size-0-input

Fixes #683. Feature/issue 683 size 0 input