fix: Add support for multi-level filenames

lib/config/exec.js

@@ -155,7 +155,9 @@ function exec(nodemonOptions, execMap) {
   // BIG NOTE: user can't do this: nodemon -e *.js
   // because the terminal will automatically expand the glob against
   // the file system :(
-  extension = (extension.match(/[^,.\s]+/g) || []).join(',');
+  extension = (extension.match(/[^,*\s]+/g) || [])
+    .map(ext => ext.replace(/^\./, ''))
+    .join(',');
 
   options.ext = extension;