kubectl_installation_script.sh

#!/bin/bash
############################
## Edited by TdlMatias ##### 
############################
# Script to install Kubectl
############################

KUBECTL_BIN=kubectl 

function install_kubectl {
    if [ -z $(which $KUBECTL_BIN) ]
        then
            curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/$KUBECTL_BIN
            chmod +x ${KUBECTL_BIN}
            sudo mv ${KUBECTL_BIN} /usr/local/bin/${KUBECTL_BIN}
    else
        echo "Kubectl is most likely installed"
    fi     
}

Please test it before use it ... :-) All feed backs are welcome