remove ensure_vm_exists command helper as it's no longer needed

lib/fission/command_helpers.rb

@@ -1,23 +1,5 @@
 module Fission
   module CommandHelpers
 
-    # Public: Checks for the existence of a VM.
-    #
-    # vm - Fission VM object to look for.
-    #
-    # Examples
-    #
-    #   ensure_vm_exists 'foo'
-    #
-    # Returns nothing.
-    # If the VM does not exist, then an error will be output and it will exit
-    # with an exit code of 1.
-    # If the VM exists, nothing will be output.
-    def ensure_vm_exists(vm)
-      unless vm.exists?
-        output_and_exit "Unable to find the VM '#{vm.name}' (#{VM.path(vm.name)})", 1
-      end
-    end
-
   end
 end

spec/fission/command_helpers_spec.rb

@@ -8,27 +8,4 @@
     @object.extend Fission::CommandHelpers
   end
 
-  describe 'ensure_vm_exists' do
-    before do
-      @vm_mock.stub(:name).and_return('foo')
-    end
-
-    it 'should output and exit if the VM does not exist' do
-      @vm_mock.should_receive(:exists?).and_return(false)
-      @object.should_receive(:output_and_exit).
-              with("Unable to find the VM 'foo' (#{Fission::VM.path('foo')})", 1)
-
-      @object.ensure_vm_exists @vm_mock
-    end
-
-    it 'should do nothing if the VM exists' do
-      @vm_mock.should_receive(:exists?).and_return(true)
-      @object.should_not_receive(:output_and_exit)
-      @object.should_not_receive(:output)
-
-      @object.ensure_vm_exists @vm_mock
-    end
-
-  end
-
 end