* Added --current flag to set-context command to use current-context
when context not provided
* Added validation to throw error when both context and --current flag
* Updated golden files to match the recent change
given
* Added validation to check if current context is set when --current
flag is provided
Old Format: airshipctl config set-context default --manifest default --namespace default
New Format: airshipctl config set-context --current --manifest default --namespace default
Change-Id: I9ffe3a34f33ffd7ff03ca42de7609f91f5386b37