Check if gun data missing for entire line.

The `sequences` object now carries the attribute
`has_smsrc_data`, a boolean which is true iff
there is at least one `smsrc` record in the raw
shots metadata.

This is used by:

1. A new sequence-wise test which reports if gun
   data is missing for the entire sequence.

2. The individual `missing_gun_data` test which
   is inhibited if `has_smsrc_data` for the
   corresponding sequence is false.

Closes #93.

etc/qc/default/definitions.yaml

@@ -20,11 +20,20 @@
     disabled: false
     labels: [ "QC", "QCGuns" ]
     children:
+        -
+            name: "Sequences without gun data"
+            iterate: "sequences"
+            id: seq_no_gun_data
+            check: |
+                const sequence = currentItem;
+                currentItem.has_smsrc_data || "Sequence has no gun data"
         -
             name: "Missing gun data"
             id: missing_gun_data
             check: |
-                !!currentItem._("raw_meta.smsrc.guns") || "Missing gun data"
+                sequences.some(s => s.sequence == currentItem.sequence && s.has_smsrc_data)
+                    ? (!!currentItem._("raw_meta.smsrc.guns") || "Missing gun data")
+                    : true
 
         -
             name: "No fire"