vendor: updated go-jwt to use semver instead of gopkg

Author: Aeneas Rekkas (arekkas)

glide.yaml

@@ -2,6 +2,7 @@ package: github.com/ory-am/fosite
 import:
 - package: github.com/asaskevich/govalidator
 - package: github.com/dgrijalva/jwt-go
+  version: ~2.7.0
 - package: github.com/go-errors/errors
 - package: github.com/golang/mock
   subpackages:

token/jwt/jwt.go

@@ -9,7 +9,7 @@ import (
 	"strings"
 
 	"github.com/pkg/errors"
-	"gopkg.in/dgrijalva/jwt-go.v2"
+	"github.com/dgrijalva/jwt-go"
 )
 
 // Enigma is responsible for generating and validating challenges.