fix #52 gush branch:delete command now supports other_organization

                   
|Q            |A  |
|---          |---|
|Bug Fix?     |yes|
|New Feature? |no |
|BC Breaks?   |no |
|Deprecations?|no |
|Tests Pass?  |yes|
|Fixed Tickets|#52|
|License      |MIT|
|Doc PR       |na |
                   

added other_organization argument to override the username from the adapter authentication that is usually the default