added demo generator

demo/demo.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+prompt() {
+    if test -n "$1"; then
+        echo
+        echo -n "% $*"
+        sleep 1
+        echo
+        $*
+        echo
+        echo -n "% "
+    else
+        echo -n "% "
+    fi
+}
+
+PATH=..:$PATH
+clear
+while IFS=$'\t' read -r flags table msg source _; do
+    echo "#"
+    echo "#   source tabular data:"
+    cat $table
+    echo
+    echo "#"
+    echo "#   $msg:"
+    prompt "tablizer $flags $table"
+  
+    sleep 4
+    clear
+done < <(yq -r tables.yaml \
+         | yq -r '.tables[] | [.flags, .table, .msg, .source] | @tsv')