build: added option to run mage without installing it

.travis.yml

@@ -20,12 +20,11 @@ os:
 
 install:
   - curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.26.0
-  - go get github.com/magefile/mage
 
 script:
   - go mod download
   - go mod verify
-  - mage -v check
+  - go run mage.go -v check
 
 after_success:
   - bash <(curl -s https://codecov.io/bash)

README.md

@@ -29,12 +29,9 @@ To build a binary from the source code, you need to have [Go](https://golang.org
 
 **Steps**:
 1. Clone repository: `git clone https://github.com/g1ntas/accio`
-2. Build: `go build`
+2. Build: `go run mage.go build`
 3. Run `./accio` to verify if it works
 
-**NOTE**:  
-While it’s the easiest way to build a binary, it doesn’t include any versioning information. For best results, use [Mage](https://magefile.org/) with `mage build`.
-
 ## Quickstart
 ### Running generator
 You can run a generator from a local directory with `run` command:

mage.go

@@ -0,0 +1,12 @@
+// +build ignore
+
+package main
+
+import (
+	"github.com/magefile/mage/mage"
+	"os"
+)
+
+func main() {
+	os.Exit(mage.Main())
+}