Add 18.04 docker file support and docker install commands in README

Change-Id: Ibf80978f2e9a3077841d9052ce4839e81312f215

Dockerfile_18.04

+# Get base OS from Ubunut
+FROM ubuntu:18.04
+
+ENV DEBIAN_FRONTEND=noninteractive
+# Update system
+RUN apt update
+
+# Install sudo for installing other packages
+RUN apt install -y sudo
+
+# Install below yocto system requirements for buiding yocto on 18.04 OS
+RUN apt install -y gawk wget git diffstat unzip texinfo gcc build-essential chrpath socat \
+    cpio python3 python3-pip python3-pexpect xz-utils debianutils iputils-ping python3-git \
+    python3-jinja2 libegl1-mesa libsdl1.2-dev python3-subunit mesa-common-dev zstd \
+    liblz4-tool file locales libacl1
+
+# Setup locales
+RUN locale-gen en_US.UTF-8
+RUN update-locale LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8
+
+ENV LANG en_US.UTF-8
+ENV LANGUAGE en_US:en
+ENV LC_ALL en_US.UTF-8
+
+# Install curl for downloading the repo
+RUN apt install -y curl
+
+# Run below command to download the opensource repo
+RUN curl https://storage.googleapis.com/git-repo-downloads/repo -o /usr/local/bin/repo
+
+# Run below command to make repo executable for all users
+RUN chmod a+x /usr/local/bin/repo
+
+# Export repo path to system path variable
+RUN export PATH=/usr/local/bin:$PATH
+
+# Install vim file editor inside the container
+RUN apt install -y vim
+
+# Change python version system-wide with update-alternatives python
+# 20.04 default python version is 3.6
+RUN update-alternatives --install /usr/bin/python python /usr/bin/python3.6 1
+
+# Change your /bin/sh symlink to point to bash yocto build environment needed bash
+RUN ln -sf /bin/bash /bin/sh
+
+# Export UID and GID in container
+ARG USER
+ARG WORKDIR
+ARG UID
+ARG GID
+RUN groupadd -g $GID -o $USER
+RUN useradd -m -u $UID -g $GID -o -s /bin/bash $USER
+
+WORKDIR $WORKDIR
+
+USER $USER
+# Run below commands if you haven't setup gitconfig
+RUN git config --global user.email $USER@example.com
+RUN git config --global user.name $USER
+RUN git config --global color.ui auto

README.md

+# Before running docker commands your system needs docker installation please follow below steps
+# if you haven't installed the docker
+
+# Install docker Using the installation script
+  $ curl -fsSL https://get.docker.com -o get-docker.sh
+# Run the docker.sh script
+  $ sudo sh get-docker.sh
+# Setting docker Engine permission on Ubuntu
+  $ sudo groupadd docker
+  $ sudo usermod -aG docker $USER
+# set permission to the docker file
+  $ sudo chown $USER:$USER /home/$USER/.docker -R
+  $ sudo chmod g+rwx $HOME/.docker -R
+# Try running below test command
+  $ docker run hello-world
+
 # Source release env variables
-# Supported Dockerfiles ( Dockerfile_20.04, Dockerfile_22.04 )
+# Supported Dockerfiles ( Dockerfile_18.04, Dockerfile_20.04 )
 source qcom-6.6.00-QLI.1.0-Ver.1.0/config.sh <Dockerfile>
 
 # Docker help commands