Make default commenting system optional

Update blah (setup) to ask for an email to broadcast for accepting
comments.

If no eMail is provided, the default commenting system is shut off and
the commenting page is not compiled

Update commenting page to use the new variable (not hardcoded eMail
specific to author of software...)

Update testSetup.sh to allow for the new variable to autosetup blah with
default commenting system enabled

Update tail.tmpl to only show the commenting section if we can handle
comments
Update commenting page contents and comments.tmpl

Reduced wall of text as much as possible

Update comments.tmpl to be minimalistic as well