example of variables usage for gitversion execute for azure pipelines

docs/examples/azure/gitversion/execute.md

@@ -0,0 +1,10 @@
+# Example
+
+```yaml
+  steps:
+  - task: gitversion/execute@0
+    displayName: Use GitVersion
+  - script: |
+      echo "FullSemVer: $(fullSemVer)"
+      echo "##vso[build.updatebuildnumber]$(fullSemVer)"
+```

docs/examples/azure/gitversion/setup.md

@@ -0,0 +1,9 @@
+# Example
+
+```yaml
+  steps:
+  - task: gitversion/setup@0
+    displayName: Install GitVersion
+    inputs:
+    versionSpec: '5.1.2'
+```