Remove the undocumented "find nearest template" feature when registering

[dfreedm]

If you have

<template is="dom-bind">
<template is="dom-repeat">
</template>
</template>

in index.html, and use an external script for polymer via crisper, dom-repeat and dom-bind will find the top level dom-bind template as their shadowdom templates and recursively expand until the stack explodes.