Replace makeStaticLoader with a grunt task

'grunt build' builds modules/ve/test/index.php, demos/ve/index.php
and .docs/eg-iframe.html from the associated *.template files.

Got rid of the JS-based SVG/PNG switching logic. Instead, we now
just use SVG unconditionally. We'd already dropped browser support
for browsers that don't support SVG anyway.

Change-Id: Iba2e68f17904687cb13e793a410e095f28f1b13c
Merge "Replace makeStaticLoader with a grunt task"