Snapcraft yaml for Azure CLI (Azure#5904)

* snapcraft.yaml

* add version

.snapcraft.yaml

@@ -0,0 +1,42 @@
+name: azure-cli
+summary: Microsoft Azure CLI 2.0
+description: |
+ A great cloud needs great tools; we're excited to introduce Azure CLI 2.0, our
+ next generation multi-platform command line experience for Azure.
+version: "release"
+version-script: |
+ grep VERSION src/azure-cli/setup.py | head -n 1 | cut -d'"' -f2
+confinement: classic
+grade: stable
+apps:
+  az:
+    command: usr/bin/python -m azure.cli
+    completer: az.completion
+parts:
+  azure-cli:
+    plugin: python
+    source: .
+    python-version: python3
+    build-packages:
+      - build-essential
+      - python3-dev
+      - python3-wheel
+      - libffi-dev
+      - libssl-dev
+    stage-packages:
+      - libffi6
+      - libssl1.0.0
+    requirements: requirements.txt
+    install: |
+      python_packages="src/azure-cli-core src/azure-cli-nspkg src/azure-cli-command_modules-nspkg src/command_modules/azure-cli*"
+      export PYTHONUSERBASE=$SNAPCRAFT_PART_INSTALL
+      export PYTHONHOME=$SNAPCRAFT_PART_INSTALL/usr
+      echo $SNAPCRAFT_PART_INSTALL/usr/bin/python3
+      $SNAPCRAFT_PART_INSTALL/usr/bin/python3 -c 'import site; print("PYTHONUSERBASE set to {!r}".format(site.getuserbase()))'
+      $SNAPCRAFT_PART_INSTALL/usr/bin/python3 -m pip install --user $python_packages
+      $SNAPCRAFT_PART_INSTALL/usr/bin/python3 -m pip install --no-index --user src/azure-cli
+      install build_scripts/snap/az.snap.completion $SNAPCRAFT_PART_INSTALL/az.completion
+      # PEP 394 says you should use python3, but the client uses python.
+      ln -s python3 $SNAPCRAFT_PART_INSTALL/usr/bin/python
+    prime:
+      - -lib/python3.5/site-packages/tabulate-0.7.7.dist-info/.PKG-INFO.swp

build_scripts/snap/az.snap.completion

@@ -0,0 +1,21 @@
+_python_argcomplete() {
+    local IFS=$'\013'
+    local SUPPRESS_SPACE=0
+    if compopt +o nospace 2> /dev/null; then
+        SUPPRESS_SPACE=1
+    fi
+    COMPREPLY=( $(IFS="$IFS" \
+                  COMP_LINE="$COMP_LINE" \
+                  COMP_POINT="$COMP_POINT" \
+                  COMP_TYPE="$COMP_TYPE" \
+                  _ARGCOMPLETE_COMP_WORDBREAKS="$COMP_WORDBREAKS" \
+                  _ARGCOMPLETE=1 \
+                  _ARGCOMPLETE_SUPPRESS_SPACE=$SUPPRESS_SPACE \
+                  "$SNAP/usr/bin/python" -m azure.cli 8>&1 9>&2 1>/dev/null 2>/dev/null) )
+    if [[ $? != 0 ]]; then
+        unset COMPREPLY
+    elif [[ $SUPPRESS_SPACE == 1 ]] && [[ "$COMPREPLY" =~ [=/:]$ ]]; then
+        compopt -o nospace
+    fi
+}
+complete -o nospace -F _python_argcomplete azure-cli.az