Add test instructions and fix region disk test (#500)

As a step toward adding integration testing into
the CI process for this project, adding instructions
on how to run the tests.

compute_region_disk was used as a test. Fixed
the tests which was previously hard-coded to
the `graphite-playground` GCP project to work
with the project in the user-configure .ini file.

tests/integration/targets/gcp_compute_region_disk/aliases

@@ -1,2 +1 @@
-cloud/gcp
-unsupported
+cloud/gcp

tests/integration/targets/gcp_compute_region_disk/tasks/autogen.yml

@@ -21,8 +21,8 @@
       raw_key: SGVsbG8gZnJvbSBHb29nbGUgQ2xvdWQgUGxhdGZvcm0=
     region: us-central1
     replica_zones:
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-a
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-b
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-a
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-b
     project: "{{ gcp_project }}"
     auth_kind: "{{ gcp_cred_kind }}"
     service_account_file: "{{ gcp_cred_file }}"
@@ -36,8 +36,8 @@
       raw_key: SGVsbG8gZnJvbSBHb29nbGUgQ2xvdWQgUGxhdGZvcm0=
     region: us-central1
     replica_zones:
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-a
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-b
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-a
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-b
     project: "{{ gcp_project }}"
     auth_kind: "{{ gcp_cred_kind }}"
     service_account_file: "{{ gcp_cred_file }}"
@@ -71,8 +71,8 @@
       raw_key: SGVsbG8gZnJvbSBHb29nbGUgQ2xvdWQgUGxhdGZvcm0=
     region: us-central1
     replica_zones:
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-a
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-b
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-a
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-b
     project: "{{ gcp_project }}"
     auth_kind: "{{ gcp_cred_kind }}"
     service_account_file: "{{ gcp_cred_file }}"
@@ -91,8 +91,8 @@
       raw_key: SGVsbG8gZnJvbSBHb29nbGUgQ2xvdWQgUGxhdGZvcm0=
     region: us-central1
     replica_zones:
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-a
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-b
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-a
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-b
     project: "{{ gcp_project }}"
     auth_kind: "{{ gcp_cred_kind }}"
     service_account_file: "{{ gcp_cred_file }}"
@@ -126,8 +126,8 @@
       raw_key: SGVsbG8gZnJvbSBHb29nbGUgQ2xvdWQgUGxhdGZvcm0=
     region: us-central1
     replica_zones:
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-a
-    - https://www.googleapis.com/compute/v1/projects/google.com:graphite-playground/zones/us-central1-b
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-a
+    - https://www.googleapis.com/compute/v1/projects/{{ gcp_project }}/zones/us-central1-b
     project: "{{ gcp_project }}"
     auth_kind: "{{ gcp_cred_kind }}"
     service_account_file: "{{ gcp_cred_file }}"