Implement git refs API for listing references (branches, tags and other) (#5354)

* Inital routes to git refs api

* Git refs API implementation

* Update swagger

* Fix copyright

* Make swagger happy add basic test

* Fix test

* Fix test again :)

vendor/gopkg.in/src-d/go-git.v4/internal/revision/token.go

@@ -0,0 +1,28 @@
+package revision
+
+// token represents a entity extracted from string parsing
+type token int
+
+const (
+	eof token = iota
+
+	aslash
+	asterisk
+	at
+	caret
+	cbrace
+	colon
+	control
+	dot
+	emark
+	minus
+	number
+	obrace
+	obracket
+	qmark
+	slash
+	space
+	tilde
+	tokenError
+	word
+)