fix bug 844528 - Disable robots on dev servers

A few things here:

0.  I've added a cron routine to create the robots.txt file
1.  I'm hard-coding the robots.txt content in the view; history shows we never touch it.
2.  I'm uploading a new, disallow-all robots.txt to replace anything on a dev server so that if they don't have CRONs already, we don't need to do a bunch of config

STOP!  TWO IMPORTANT THINGS:
1.  WE MUST MAKE SURE THAT "ENGAGE_ROBOTS" IS "True" IN PRODUCTION
2.  WE MUST RUN THIS CRON IN PRODUCTION AS SOON AS IT'S PUSHED SO WE DON'T DISALLOWING INDEXING IN PRODUCTION.  WE WOULD BE HOSED.

That is all.