Create a tools directory for an application. Add source code
stubs to allow the project to compile and pass make distcheck.
Add notes in source code to tell the user how to create plugin
or app code using the other -maker scripts.
This is a replacement for gst-template that creates an entire
autotools project (customized to package name), and populates
it with the source for a GStreamer plugin (but no plugin features,
those come from gst-element-maker). Fixes: #665727.
