Use Go1.11 module (#5743)

* Migrate to go modules

* make vendor

* Update mvdan.cc/xurls

* make vendor

* Update code.gitea.io/git

* make fmt-check

* Update github.com/go-sql-driver/mysql

* make vendor

vendor/gopkg.in/redis.v2/.travis.yml

@@ -0,0 +1,19 @@
+language: go
+
+services:
+- redis-server
+
+go:
+  - 1.1
+  - 1.2
+  - 1.3
+  - tip
+
+install:
+  - go get gopkg.in/bufio.v1
+  - go get gopkg.in/check.v1
+  - mkdir -p $HOME/gopath/src/gopkg.in
+  - ln -s `pwd` $HOME/gopath/src/gopkg.in/redis.v2
+
+before_script:
+  - redis-server testdata/sentinel.conf --sentinel &

vendor/gopkg.in/redis.v2/Makefile

@@ -0,0 +1,3 @@
+all:
+	go test gopkg.in/redis.v2 -cpu=1,2,4
+	go test gopkg.in/redis.v2 -short -race

vendor/gopkg.in/redis.v2/README.md

@@ -0,0 +1,46 @@
+Redis client for Golang [![Build Status](https://travis-ci.org/go-redis/redis.png?branch=master)](https://travis-ci.org/go-redis/redis)
+=======================
+
+Supports:
+
+- Redis 2.8 commands except QUIT, MONITOR, SLOWLOG and SYNC.
+- Pub/sub.
+- Transactions.
+- Pipelining.
+- Connection pool.
+- TLS connections.
+- Thread safety.
+- Timeouts.
+- Redis Sentinel.
+
+API docs: http://godoc.org/gopkg.in/redis.v2.
+Examples: http://godoc.org/gopkg.in/redis.v2#pkg-examples.
+
+Installation
+------------
+
+Install:
+
+    go get gopkg.in/redis.v2
+
+Look and feel
+-------------
+
+Some corner cases:
+
+    SORT list LIMIT 0 2 ASC
+    vals, err := client.Sort("list", redis.Sort{Offset: 0, Count: 2, Order: "ASC"}).Result()
+
+    ZRANGEBYSCORE zset -inf +inf WITHSCORES LIMIT 0 2
+    vals, err := client.ZRangeByScoreWithScores("zset", redis.ZRangeByScore{
+        Min: "-inf",
+        Max: "+inf",
+        Offset: 0,
+        Count: 2,
+    }).Result()
+
+    ZINTERSTORE out 2 zset1 zset2 WEIGHTS 2 3 AGGREGATE SUM
+    vals, err := client.ZInterStore("out", redis.ZStore{Weights: []int64{2, 3}}, "zset1", "zset2").Result()
+
+    EVAL "return {KEYS[1],ARGV[1]}" 1 "key" "hello"
+    vals, err := client.Eval("return {KEYS[1],ARGV[1]}", []string{"key"}, []string{"hello"}).Result()