add /bin/bash everywhere

shell/cat.sh

@@ -1,3 +1,5 @@
+#!/bin/bash
+
 # cat for Markdown in my ultralight writing database
 # wherein concatenated filed need a "\n---\n\n" between them.
 

shell/rename.sh

@@ -1,3 +1,5 @@
+#!/bin/bash
+
 # rename : renames the string descriptor used in numbered series.
 
 # Usage:

shell/tag.sh

@@ -1,2 +1,4 @@
+#!/bin/bash
+
 # just list the files so we can pipe it.
 grep -lE "\+ $@" *md