ClickTag usage  What is clickTag?  The clickTag variable is the
IAB's standard for linking to external URLs particularly from
flash banner ads. BannerSnack is fully compatible with clickTag,
but from version 3.0 we made clickTag optional since a lot of
our users are not familiar with it and have real problems
understanding how and why should they use clickTag.  When should
you use clickTag?  You should use clickTag if you really have
to; here are the most important cases where the clickTag
variable is a good solution:    1. To track clicks/campaigns
(use a third party tracking site to route your visitors
through).   2. To enable publishers to control where your banner
links to (potentially use their own tracking route as well).
3. To be able to change the target URL after the banner is
exported/downloaded.   4. When you develop a banner for somebody
else and you want to let them add the link later.   5. To be
able to use dynamic links (maybe send some private user data
along with their clicks from the publi