Update docker files to allow specifying pwsh and from image version (#6835)

Update docker files to allow specifying pwsh and from image version
- Also updated to install security updates when building images

docker/release/centos7/Dockerfile

@@ -1,6 +1,7 @@
 # Docker image file that describes an Centos7 image with PowerShell installed from Microsoft YUM Repo
+ARG FromTag=7
 
-FROM centos:7
+FROM centos:${FromTag}
 
 ARG POWERSHELL_VERSION=6.0.2
 ARG IMAGE_NAME=microsoft/powershell:centos7
@@ -38,7 +39,7 @@ RUN curl https://packages.microsoft.com/config/rhel/7/prod.repo | tee /etc/yum.r
 
 # Install latest powershell from Microsoft YUM Repo
 RUN yum install -y \
-        powershell \
+        powershell-${POWERSHELL_VERSION} \
     && yum clean all
 
 # Use PowerShell as the default shell

docker/release/fedora26/Dockerfile

@@ -1,6 +1,7 @@
 # Docker image file that describes an fedora 25 image with PowerShell installed from Microsoft YUM Repo
+ARG FromTag=26
 
-FROM fedora:26
+FROM fedora:${FromTag}
 
 ARG POWERSHELL_VERSION=6.0.2
 ARG IMAGE_NAME=microsoft/powershell:fedora26
@@ -38,7 +39,7 @@ RUN localedef --charmap=UTF-8 --inputfile=en_US $LANG
 RUN curl https://packages.microsoft.com/config/rhel/7/prod.repo | tee /etc/yum.repos.d/microsoft.repo
 
 # Install latest powershell from Microsoft YUM Repo
-RUN dnf install -y powershell \
+RUN dnf install -y powershell-${POWERSHELL_VERSION} \
     && dnf clean all
 
 # Use array to avoid Docker prepending /bin/sh -c

docker/release/fedora27/Dockerfile

@@ -1,6 +1,7 @@
 # Docker image file that describes an fedora 27 image with PowerShell installed from Microsoft YUM Repo
+ARG FromTag=27
 
-FROM fedora:27
+FROM fedora:${FromTag}
 
 ARG POWERSHELL_VERSION=6.0.2
 ARG IMAGE_NAME=microsoft/powershell:fedora27
@@ -39,7 +40,7 @@ RUN localedef --charmap=UTF-8 --inputfile=en_US $LANG
 RUN curl https://packages.microsoft.com/config/rhel/7/prod.repo | tee /etc/yum.repos.d/microsoft.repo
 
 # Install latest powershell from Microsoft YUM Repo
-RUN dnf install -y powershell \
+RUN dnf install -y powershell-${POWERSHELL_VERSION}} \
     && dnf clean all
 
 # Use array to avoid Docker prepending /bin/sh -c

docker/release/opensuse42.2/Dockerfile

@@ -1,6 +1,7 @@
 # Docker image file that describes an OpenSUSE 42.2 image with PowerShell installed from PowerShell Release
+ARG FromTag=42.2
 
-FROM opensuse:42.2
+FROM opensuse:${FromTag}
 
 ARG POWERSHELL_VERSION=6.0.2
 ARG POWERSHELL_PACKAGE=powershell-6.0.2-linux-x64.tar.gz

docker/release/ubuntu14.04/Dockerfile

@@ -1,8 +1,10 @@
 # Docker image file that describes an Ubuntu14.04 image with PowerShell installed from Microsoft APT Repo
+ARG FromTag=14.04
 
-FROM ubuntu:trusty
+FROM ubuntu:${FromTag}
 
 ARG POWERSHELL_VERSION=6.0.2
+ARG POWERSHELL_VERSION_POSTFIX=-1.ubuntu.14.04
 ARG IMAGE_NAME=microsoft/powershell:ubuntu14.04
 
 LABEL maintainer="PowerShell Team <powershellteam@hotmail.com>" \
@@ -34,6 +36,8 @@ RUN apt-get update \
         ca-certificates \
         curl \
         apt-transport-https \
+    && apt-get dist-upgrade -y \
+    && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
 
 # Import the public repository GPG keys for Microsoft
@@ -45,7 +49,9 @@ RUN curl https://packages.microsoft.com/config/ubuntu/14.04/prod.list | tee /etc
 # Install powershell from Microsoft Repo
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-	powershell
+	powershell=${POWERSHELL_VERSION}${POWERSHELL_VERSION_POSTFIX} \
+    && apt-get clean \
+    && rm -rf /var/lib/apt/lists/*
 
 # Use PowerShell as the default shell
 # Use array to avoid Docker prepending /bin/sh -c

docker/release/ubuntu16.04/Dockerfile

@@ -1,8 +1,10 @@
 # Docker image file that describes an Ubuntu16.04 image with PowerShell installed from Microsoft APT Repo
+ARG FromTag=16.04
 
-FROM ubuntu:xenial
+FROM ubuntu:${FromTag}
 
 ARG POWERSHELL_VERSION=6.0.2
+ARG POWERSHELL_VERSION_POSTFIX=-1.ubuntu.16.04
 ARG IMAGE_NAME=microsoft/powershell:ubuntu16.04
 
 LABEL maintainer="PowerShell Team <powershellteam@hotmail.com>" \
@@ -29,7 +31,9 @@ RUN apt-get update \
         ca-certificates \
         curl \
         apt-transport-https \
-        locales\
+        locales \
+    && apt-get dist-upgrade -y \
+    && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
 
 # Setup the locale
@@ -46,7 +50,9 @@ RUN curl https://packages.microsoft.com/config/ubuntu/16.04/prod.list | tee /etc
 # Install powershell from Microsoft Repo
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \
-	powershell
+    powershell=${POWERSHELL_VERSION}${POWERSHELL_VERSION_POSTFIX} \
+    && apt-get clean \
+    && rm -rf /var/lib/apt/lists/*
 
 # Use PowerShell as the default shell
 # Use array to avoid Docker prepending /bin/sh -c