Add tags field to Bolt task metadata schema

This commit adds the `tags` field to Bolt task metadata. A description
of why a `tags` field would be useful is included in the
`tasks/README.md` update.

Author: hsnodgrass

tasks/README.md

@@ -84,6 +84,7 @@ The preferred style of the keys should be `snake_case`.
 
 **remote**: Default `false`. All implementation of this task operate on a remote target using the `_target` metaparam.(rev 4)
 
+**tags**: An array of strings used for arbitrary tags without inherent, semantic meaning to a task runner. Useful for categorizing tasks.
 
 #### Example Task Metadata
 
@@ -114,7 +115,8 @@ The preferred style of the keys should be `snake_case`.
     {"name": "foo_sh.sh", "requirements": ["shell"], "input_method": "environment"},
     {"name": "foo_ps1.ps1", "requirements": ["powershell"], "files": ["my_util/files/util/win_tools.ps1"]}
   ],
-  "files": ["my_module/lib/puppet_x/helpful_code.rb", "kitchensink/files/task_helpers/"]
+  "files": ["my_module/lib/puppet_x/helpful_code.rb", "kitchensink/files/task_helpers/"],
+  "tags": ["tag1", "Tag 2", "Three"]
 }
 ```
 

tasks/task.json

@@ -77,6 +77,13 @@
       "items": {
         "type": "object"
       }
+    },
+    "tags": {
+      "type": "array",
+      "items": {
+        "type": "string"
+      },
+      "description": "Arbitrary tags without inherent, semantic meaning."
     }
   },
   "definitions": {