make sure both headers are set before checking for ip spoofing
"generates" applies to "collection radio" so it should be singular
take out reference to previous versions of Rails
Revert ""generates" applies to "collection radio" so it should be singular"

This reverts commit faeb33dc036e4f707491c91a23ee3e990573141b.

Reason: Code changes can't be done on docrails
Updated with latest method [ci skip]
Updated the file path [ci skip]
Updated guides with latest method [ci skip]
Removed doc of diff method [ci skip]
asset_url => asset-url in sass-rails docs [ci skip]
EncryptedCookieStore => CookieStore [ci skip]
Remove HelperyTestHelper not used in any test

HelperyTestHelper was introduced in 66ef922 by @josevalim
to pair with HelperyTestController. This test controller was
later removed in e10a253 by @strzalek, leaving HelperyTestHelper unused
surplus : in attachment_fu plugin

surplus ':' character in url
incorrect urls 

I've found two incorrects urls for adding ':' at the end of the url
incorrect url

incorrect url
Fix Show link on resource
`skiping` => `skipping`
exposing target records on the preloader
do not access internal data structures
generate fewer objects when grouping
extract exception raising, clean up group_by statement