remove script elements

we don't want scripts to run because they might change
the page content which should be stay frozen the same
as when the page was snapshotted.
imageSnap method for debugging and testing

this simplifies debugging by automatically opening the
returned image in a new window. However, calling this
from the console will trigger a javascript popup, which
browsers will block, so you need to enable popups on 
the domain.
htmlSnap: useful for debugging

it opens the snapshotted html content in a new window
Merge branch 'wip-htmlSnap-and-optimize'
Version 0.2.2