mCoffee brew per Thaddaeus

Testing version of mCoffee. This extension is for testing the next version of mCoffee.

https://addons.mozilla.org/en-US/firefox/addon/mcoffee/

Changes from current version of mCoffee.

- initially limit concurrent loading tabs of tabs to 3. If a site takes more than 15 seconds to complete loading, don't wait for it and continuing loading the next url (if any)
- additional checks for already loaded sites to handle accidental double clicks.

Disclaimer
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I wrote this extension for my own use but am making it available to the public in case someone else finds it useful.

THIS EXTENSION IS PROVIDED IN GOOD FAITH, HOWEVER I MAKE NO REPRESENTATION OR WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, REGARDING THE ACCURACY, ADEQUACY, VALIDITY, RELIABILITY, AVAILABILITY, FUNCTIONALITY OR COMPLETENESS OF ANY INFORMATION ON THE EXTENSION.

UNDER NO CIRCUMSTANCE SHALL I HAVE ANY LIABILITY TO YOU FOR ANY LOSS OR DAMAGE OF ANY KIND INCURRED AS A RESULT OF THE USE OF THIS EXTENSION.

YOUR USE OF THE EXTENSION IS SOLELY AT YOUR OWN RISK.