Bug 1413928 - [tryselect] Create a new argument group for 'task' arguments r=maja_zf

This simply groups arguments related to generating the list of
tasks from taskgraph into their own argument group.

MozReview-Commit-ID: IHRXXi5mB4G

tools/tryselect/cli.py

@@ -58,6 +58,19 @@ COMMON_ARGUMENT_GROUPS = {
           'help': 'Edit the preset file.',
           }],
     ],
+    'task': [
+        [['--full'],
+         {'action': 'store_true',
+          'default': False,
+          'help': "Use the full set of tasks as input to fzf (instead of "
+                  "target tasks).",
+          }],
+        [['-p', '--parameters'],
+         {'default': None,
+          'help': "Use the given parameters.yml to generate tasks, "
+                  "defaults to latest parameters.yml from mozilla-central",
+          }],
+    ],
 }