add 301 redirects before filter

add scaffold for permanent redirects
add before_filter approach
add validation for different origin and destination
add 301 status code to perm redirects
add unique redirect constraint validation
add circular redirection validation
ouch! rails version conflict
leave record_not_found to main_app
add instructions for usage to README
Merge pull request #1 from the-undefined/permanent-redirect

Permanent redirects