Add stub for doll-master and doll services, add required vendored libs

vendor/github.com/carlmjohnson/requests/errorkind_string.go

@@ -0,0 +1,27 @@
+// Code generated by "stringer -type=ErrorKind"; DO NOT EDIT.
+
+package requests
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[ErrURL-0]
+	_ = x[ErrRequest-1]
+	_ = x[ErrTransport-2]
+	_ = x[ErrValidator-3]
+	_ = x[ErrHandler-4]
+}
+
+const _ErrorKind_name = "ErrURLErrRequestErrTransportErrValidatorErrHandler"
+
+var _ErrorKind_index = [...]uint8{0, 6, 16, 28, 40, 50}
+
+func (i ErrorKind) String() string {
+	if i < 0 || i >= ErrorKind(len(_ErrorKind_index)-1) {
+		return "ErrorKind(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _ErrorKind_name[_ErrorKind_index[i]:_ErrorKind_index[i+1]]
+}