License Plugin: Added a "setup" action to the REST test for delete

The delete test has been relying on the license already being installed
in the cluster from the other test. However, many runners run tests
in arbitrary order, so it has been failing.

This patch adds a "Trial Development" license as the first action
in the test.

Related: elastic/elasticsearch#2777

Closes elastic/elasticsearch#2778

Original commit: elastic/x-pack-elasticsearch@cd198cf67a

elasticsearch/x-pack/license-plugin/src/test/resources/rest-api-spec/test/license/20_put_license.yaml

@@ -61,12 +61,18 @@
 
 ---
 "Should throw 404 after license deletion":
+  - do:
+      xpack.license.post:
+        acknowledge: true
+        body: |
+          {"licenses":[{"uid":"894371dc-9t49-4997-93cb-8o2e3r7fa6a8","type":"trial","issue_date_in_millis":1411948800000,"expiry_date_in_millis":1916956799999,"max_nodes":1,"issued_to":"issuedTo","issuer":"issuer","signature":"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"}]}
+
 
   - do:
-    license.delete: {}
+      xpack.license.delete: {}
 
   - match: { acknowledged: true }
 
   - do:
-      catch: missing
       license.get: {}
+      catch: missing