Reload the Mechanize object on HTTP failure

Place all HTTP transactions into one large while-try loop, so that if
any error occurs, the entire process is started.  Usually the 'br'
varible becomes unusable if there's any error.

We still occasionally get errors like this one:

	URL Error <urlopen error [Errno 8] _ssl.c:504: EOF occurred
	in violation of protocol>

but now we recover completely from them.  Note that on a General Error,
we display the contents of the 'br' variable, for debugging purposes.

The script also now tells us how many minutes it waits between passes.

Change-Id: Ie032221123b748ea25f5d5439800956c7fc9c004
Signed-off-by: Timur Tabi <timur@tabi.org>