Fix the mw.loader when running test with a file:// URL

Fix the mw.loader when running test with a file:// URL

When running the tests using a local url, the href will include index.html
which was not stripped by the regular expression.  This patch capture path
tokens which are not followed by 'index.html' (regexp lookahead).

Let us run tests using file://path/tests/qunit/index.html