[boom] add 'boom cache list -VV' command

Grab the output of 'boom cache list': it's more readable than the
cacheindex.json metadata file and displays the status of cached files.

Resolves: #4098

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>

Author: bmr-cymru

sos/report/plugins/boom.py

@@ -37,7 +37,8 @@ def setup(self):
 
         self.add_cmd_output([
             "boom list -VV",
-            "boom profile list -VV"
+            "boom cache list -VV",
+            "boom profile list -VV",
         ])
 
 # vim: set et ts=4 sw=4 :