Readme - add brute-force protection examples links

[animir]

Passport Local Strategy is one of the most used for local authentication. It would be good, if it has this note about Brute-Force protection necessity to make the web safer place.

Checklist

• I have read the CONTRIBUTING guidelines.
• I have added test cases which verify the correct operation of this feature or patch.
• I have added documentation pertaining to this feature or patch.
• The automated test suite ($ make test) executes successfully.
• The automated code linting ($ make lint) executes successfully.

[coveralls]

Coverage remained the same at 97.619% when pulling 6021a6c on animir:patch-1 into 2bf3939 on jaredhanson:master.