Add empty v1alpha2 package 🎐

This adds an empty v1alpha2 package, which serve as the base to port
v1alpha1 types to v1alpha2 while still being able to work on
v1alpha1 *and* do the appropriate refactoring while doing this.

Signed-off-by: Vincent Demeester <vdemeest@redhat.com>

hack/update-codegen.sh

@@ -30,7 +30,7 @@ KNATIVE_CODEGEN_PKG=${KNATIVE_CODEGEN_PKG:-$(cd ${REPO_ROOT_DIR}; ls -d -1 ./ven
 #                  instead of the $GOPATH directly. For normal projects this can be dropped.
 ${CODEGEN_PKG}/generate-groups.sh "deepcopy,client,informer,lister" \
   github.com/tektoncd/pipeline/pkg/client github.com/tektoncd/pipeline/pkg/apis \
-  pipeline:v1alpha1 \
+  "pipeline:v1alpha1,v1alpha2" \
   --go-header-file ${REPO_ROOT_DIR}/hack/boilerplate/boilerplate.go.txt
 
 # Depends on generate-groups.sh to install bin/deepcopy-gen
@@ -42,7 +42,7 @@ ${GOPATH}/bin/deepcopy-gen \
 # Knative Injection
 ${KNATIVE_CODEGEN_PKG}/hack/generate-knative.sh "injection" \
   github.com/tektoncd/pipeline/pkg/client github.com/tektoncd/pipeline/pkg/apis \
-  "pipeline:v1alpha1" \
+  "pipeline:v1alpha1,v1alpha2" \
   --go-header-file ${REPO_ROOT_DIR}/hack/boilerplate/boilerplate.go.txt
 
 # Make sure our dependencies are up-to-date

pkg/apis/pipeline/v1alpha2/task_types.go

@@ -0,0 +1,17 @@
+/*
+Copyright 2019 The Tekton Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package v1alpha2