Add additional checks

Checking for unencoded &amp; in ing and href.  Check for spacer.gif and
check for script or style tags with no type defined.
Comment out check for unencoded &

It seems some (most?) browsers convert &amp; to & behind the scenes
upon render, thereby making this condition fail for any URL with “&” in
it (encoded or not).  Commenting out since this is still a good check,
but is causing false positives.
Merge pull request #244 from imbrianj/master

Add additional checks for markup-test.js