Build: make bra a local dependency (#17414)

Same idea as with the `gosec`, `revive` and etc.
Allows you to execute `make bra` as pinned local dependency instead
as global one. And therefore alleviates dependency installation issues.

README also updated - I was thinking to provide verbose installation instructions
for it. Since with that way we assume make is installed on the
developer system.

But it might be premature right now?

README.md

@@ -27,7 +27,6 @@ the latest master builds [here](https://grafana.com/grafana/download)
 ### Dependencies
 
 - Go (Latest Stable)
-  - bra [`go get github.com/Unknwon/bra`]
 - Node.js LTS
   - yarn [`npm install -g yarn`]
 
@@ -40,23 +39,6 @@ go get github.com/grafana/grafana
 cd $GOPATH/src/github.com/grafana/grafana
 ```
 
-### Building
-
-#### The backend
-
-```bash
-go run build.go setup
-go run build.go build
-```
-
-#### Frontend assets
-
-_For this you need Node.js (LTS version)._
-
-```bash
-yarn install --pure-lockfile
-```
-
 ### Run and rebuild on source change
 
 #### Backend
@@ -64,7 +46,7 @@ yarn install --pure-lockfile
 To run the backend and rebuild on source change:
 
 ```bash
-$GOPATH/bin/bra run
+make run
 ```
 
 #### Frontend
@@ -93,6 +75,23 @@ yarn jest
 
 **Open grafana in your browser (default: e.g. `http://localhost:3000`) and login with admin user (default: `user/pass = admin/admin`).**
 
+### Building
+
+#### The backend
+
+```bash
+go run build.go setup
+go run build.go build
+```
+
+#### Frontend assets
+
+_For this you need Node.js (LTS version)._
+
+```bash
+yarn install --pure-lockfile
+```
+
 ### Building a Docker image
 
 There are two different ways to build a Grafana docker image. If your machine is setup for Grafana development and you run linux/amd64 you can build just the image. Otherwise, there is the option to build Grafana completely within Docker.