Step 3 - Init and create the metricset failure

@pierhugues @ruflin I was finally able to create my module and metricset by modifying the procedure and a makefile,

Following is the revised recipe that works.
All changes that I had to do are indicated with *** in my comments.

export GOPATH=~/workspace/metricbeat 

# *** 1) Must issue this export variable to fix the mix useage of python 2.7 and python 3 during "make setup"
export VIRTUALENV_PARAMS="-p python2.7" 


mkdir ~/workspace
cd ~/workspace
rm -rf metricbeat

go get github.com/elastic/beats/metricbeat
python ${GOPATH}/src/github.com/elastic/beats/script/generate.py --type=metricbeat
    Questions:
        Beat Name [Examplebeat]: metricbeat_
        Your Github Name [your-github-name]: my-github-name
        Beat Path [github.com/my-github-name/metricbeat]: github.com/my-githubname/beats/metricbeat
        Firstname Lastname: Abc Def_

cd metricbeat/src/github.com/my-github-name/beats/metricbeat/ 

# *** 2) Must do manually the following command to fix the first fatal erreor - "ImportError: No module named generate_imports_helper"
cp -r $GOPATH/src/github.com/elastic/beats/metricbeat/scripts .   # Important to fix problem 1
  
  
# *** 3) Edit the the following file: 
    nano ${GOPATH}/src/github.com/elastic/beats/metricbeat/Makefile_
# *** Replace the following line in target section "kibana:"
    @-cp -r module/*/_meta/kibana _meta/
# ***with this line:
    @-cp -r ../../../elastic/beats/metricbeat/module/*/_meta/kibana _meta/

   

# Create the the module and first metricset
make setup
Module name: datapower
Metricset name: status

# Or create new metricset to_
When creating new metricsets:
    make create-metricset
    make update
    make collect