diff --git a/vendor/github.com/spf13/pflag/flag.go b/vendor/github.com/spf13/pflag/flag.go
index 5eadc84..7c058de 100644
--- a/vendor/github.com/spf13/pflag/flag.go
+++ b/vendor/github.com/spf13/pflag/flag.go
@@ -57,9 +57,9 @@
 	var ip = flag.IntP("flagname", "f", 1234, "help message")
 	var flagvar bool
 	func init() {
-		flag.BoolVarP("boolname", "b", true, "help message")
+		flag.BoolVarP(&flagvar, "boolname", "b", true, "help message")
 	}
-	flag.VarP(&flagVar, "varname", "v", 1234, "help message")
+	flag.VarP(&flagval, "varname", "v", "help message")
 Shorthand letters can be used with single dashes on the command line.
 Boolean shorthand flags can be combined with other shorthand flags.
 
@@ -160,7 +160,7 @@
 	args              []string // arguments after flags
 	argsLenAtDash     int      // len(args) when a '--' was located when parsing, or -1 if no --
 	errorHandling     ErrorHandling
-	output            io.Writer // nil means stderr; use out() accessor
+	output            io.Writer // nil means stderr; use Output() accessor
 	interspersed      bool      // allow interspersed option/non-option args
 	normalizeNameFunc func(f *FlagSet, name string) NormalizedName
 
@@ -190,6 +190,18 @@
 	Type() string
 }
 
+// SliceValue is a secondary interface to all flags which hold a list
+// of values.  This allows full control over the value of list flags,
+// and avoids complicated marshalling and unmarshalling to csv.
+type SliceValue interface {
+	// Append adds the specified value to the end of the flag value list.
+	Append(string) error
+	// Replace will fully overwrite any data currently in the flag value list.
+	Replace([]string) error
+	// GetSlice returns the flag value list as an array of strings.
+	GetSlice() []string
+}
+
 // sortFlags returns the flags as a slice in lexicographical sorted order.
 func sortFlags(flags map[NormalizedName]*Flag) []*Flag {
 	list := make(sort.StringSlice, len(flags))
@@ -243,13 +255,20 @@
 	return n(f, name)
 }
 
-func (f *FlagSet) out() io.Writer {
+// Output returns the destination for usage and error messages. os.Stderr is returned if
+// output was not set or was set to nil.
+func (f *FlagSet) Output() io.Writer {
 	if f.output == nil {
 		return os.Stderr
 	}
 	return f.output
 }
 
+// Name returns the name of the flag set.
+func (f *FlagSet) Name() string {
+	return f.name
+}
+
 // SetOutput sets the destination for usage and error messages.
 // If output is nil, os.Stderr is used.
 func (f *FlagSet) SetOutput(output io.Writer) {
@@ -346,7 +365,7 @@
 	}
 	if len(name) > 1 {
 		msg := fmt.Sprintf("can not look up shorthand which is more than one ASCII character: %q", name)
-		fmt.Fprintf(f.out(), msg)
+		fmt.Fprintf(f.Output(), msg)
 		panic(msg)
 	}
 	c := name[0]
@@ -470,7 +489,7 @@
 	}
 
 	if flag.Deprecated != "" {
-		fmt.Fprintf(f.out(), "Flag --%s has been deprecated, %s\n", flag.Name, flag.Deprecated)
+		fmt.Fprintf(f.Output(), "Flag --%s has been deprecated, %s\n", flag.Name, flag.Deprecated)
 	}
 	return nil
 }
@@ -511,7 +530,7 @@
 // otherwise, the default values of all defined flags in the set.
 func (f *FlagSet) PrintDefaults() {
 	usages := f.FlagUsages()
-	fmt.Fprint(f.out(), usages)
+	fmt.Fprint(f.Output(), usages)
 }
 
 // defaultIsZeroValue returns true if the default value for this flag represents
@@ -746,7 +765,7 @@
 
 // defaultUsage is the default function to print a usage message.
 func defaultUsage(f *FlagSet) {
-	fmt.Fprintf(f.out(), "Usage of %s:\n", f.name)
+	fmt.Fprintf(f.Output(), "Usage of %s:\n", f.name)
 	f.PrintDefaults()
 }
 
@@ -832,7 +851,7 @@
 	_, alreadyThere := f.formal[normalizedFlagName]
 	if alreadyThere {
 		msg := fmt.Sprintf("%s flag redefined: %s", f.name, flag.Name)
-		fmt.Fprintln(f.out(), msg)
+		fmt.Fprintln(f.Output(), msg)
 		panic(msg) // Happens only if flags are declared with identical names
 	}
 	if f.formal == nil {
@@ -848,7 +867,7 @@
 	}
 	if len(flag.Shorthand) > 1 {
 		msg := fmt.Sprintf("%q shorthand is more than one ASCII character", flag.Shorthand)
-		fmt.Fprintf(f.out(), msg)
+		fmt.Fprintf(f.Output(), msg)
 		panic(msg)
 	}
 	if f.shorthands == nil {
@@ -858,7 +877,7 @@
 	used, alreadyThere := f.shorthands[c]
 	if alreadyThere {
 		msg := fmt.Sprintf("unable to redefine %q shorthand in %q flagset: it's already used for %q flag", c, f.name, used.Name)
-		fmt.Fprintf(f.out(), msg)
+		fmt.Fprintf(f.Output(), msg)
 		panic(msg)
 	}
 	f.shorthands[c] = flag
@@ -897,7 +916,7 @@
 func (f *FlagSet) failf(format string, a ...interface{}) error {
 	err := fmt.Errorf(format, a...)
 	if f.errorHandling != ContinueOnError {
-		fmt.Fprintln(f.out(), err)
+		fmt.Fprintln(f.Output(), err)
 		f.usage()
 	}
 	return err
@@ -925,13 +944,16 @@
 	}
 
 	first := args[0]
-	if first[0] == '-' {
+	if len(first) > 0 && first[0] == '-' {
 		//--unknown --next-flag ...
 		return args
 	}
 
 	//--unknown arg ... (args will be arg ...)
-	return args[1:]
+	if len(args) > 1 {
+		return args[1:]
+	}
+	return nil
 }
 
 func (f *FlagSet) parseLongArg(s string, args []string, fn parseFunc) (a []string, err error) {
@@ -990,11 +1012,12 @@
 }
 
 func (f *FlagSet) parseSingleShortArg(shorthands string, args []string, fn parseFunc) (outShorts string, outArgs []string, err error) {
+	outArgs = args
+
 	if strings.HasPrefix(shorthands, "test.") {
 		return
 	}
 
-	outArgs = args
 	outShorts = shorthands[1:]
 	c := shorthands[0]
 
@@ -1044,7 +1067,7 @@
 	}
 
 	if flag.ShorthandDeprecated != "" {
-		fmt.Fprintf(f.out(), "Flag shorthand -%s has been deprecated, %s\n", flag.Shorthand, flag.ShorthandDeprecated)
+		fmt.Fprintf(f.Output(), "Flag shorthand -%s has been deprecated, %s\n", flag.Shorthand, flag.ShorthandDeprecated)
 	}
 
 	err = fn(flag, value)