Removes get_uuid_from_prev_args method

With the removal of previous web_command logic, the get_uuid_from_prev_args method has been simplified to a single command.  The method has been removed and the appropriate slices have been updated as needed.

Fixes #273
Merge pull request #278 from mtnbikenc/issue-273-refactor-get_uuid

Fixes #273 Removes get_uuid_from_prev_args method
Refactors slice_success and slice_error

The only calls to slice_success were the remove_<item> and remove_<item>_by_uuid methods in the slices. slice_success has been removed and the slices have been refactored to print the result to the console.

slice_error is only called from the slice_call method in slice.rb.  This method has been cleaned up to remove unnecessary mk_* references.  Additionally, error logging has been corrected to only log the error once, vice twice for standard errors.

Fixes #272