docs: Update README building-from-source part with the gomodule way (#…

…152)

Closes #149 

Signed-off-by: pink-lucifer <lucifer.m.wu@gmail.com>

README.md

@@ -86,8 +86,7 @@ ec91228cb105db315553499c81918258f52cee9636ea2a4821bdb8226872f54b
 
 ### Building from source
 
-If you wish to compile ORY Oathkeeper yourself, you need to install and set up [Go 1.10+](https://golang.org/) and add `$GOPATH/bin`
-to your `$PATH` as well as [golang/dep](http://github.com/golang/dep).
+If you wish to compile ORY Oathkeeper yourself, you need to install and set up [Go 1.11+](https://golang.org/).
 
 The following commands will check out the latest release tag of ORY Oathkeeper and compile it and set up flags so that `oathkeeper version`
 works as expected. Please note that this will only work with a linux shell like bash or sh.
@@ -97,12 +96,11 @@ go get -d -u github.com/ory/oathkeeper
 cd $(go env GOPATH)/src/github.com/ory/oathkeeper
 OATHKEEPER_LATEST=$(git describe --abbrev=0 --tags)
 git checkout $OATHKEEPER_LATEST
-dep ensure -vendor-only
-go install \
+GO111MODULE=on go install \
     -ldflags "-X github.com/ory/oathkeeper/cmd.Version=$OATHKEEPER_LATEST -X github.com/ory/oathkeeper/cmd.BuildTime=`TZ=UTC date -u '+%Y-%m-%dT%H:%M:%SZ'` -X github.com/ory/oathkeeper/cmd.GitHash=`git rev-parse HEAD`" \
     github.com/ory/oathkeeper
 git checkout master
-oathkeeper help
+$GOPATH/bin/oathkeeper help
 ```
 
 ## Ecosystem