Update MD037/no-space-in-emphasis to ignore emphasis on code fences and not report violations for scenarios that span an empty code fence (fixes #381).

lib/md037.js

@@ -78,11 +78,23 @@ module.exports = {
       lineMetadata(),
       (line, lineIndex, inCode, onFence, inTable, inItem, onBreak, inMath) => {
         const onItemStart = (inItem === 1);
-        if (inCode || inTable || onBreak || onItemStart || isBlankLine(line)) {
+        if (
+          inCode ||
+          onFence ||
+          inTable ||
+          onBreak ||
+          onItemStart ||
+          isBlankLine(line)
+        ) {
           // Emphasis resets when leaving a block
           resetRunTracking();
         }
-        if (inCode || onBreak || inMath) {
+        if (
+          inCode ||
+          onFence ||
+          onBreak ||
+          inMath
+        ) {
           // Emphasis has no meaning here
           return;
         }