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/github.com/edsrzf/mmap-go/.gitignore

@@ -0,0 +1,8 @@
+*.out
+*.5
+*.6
+*.8
+*.swp
+_obj
+_test
+testdata

vendor/github.com/edsrzf/mmap-go/README.md

@@ -0,0 +1,12 @@
+mmap-go
+=======
+
+mmap-go is a portable mmap package for the [Go programming language](http://golang.org).
+It has been tested on Linux (386, amd64), OS X, and Windows (386). It should also
+work on other Unix-like platforms, but hasn't been tested with them. I'm interested
+to hear about the results.
+
+I haven't been able to add more features without adding significant complexity,
+so mmap-go doesn't support mprotect, mincore, and maybe a few other things.
+If you're running on a Unix-like platform and need some of these features,
+I suggest Gustavo Niemeyer's [gommap](http://labix.org/gommap).