The reason behind this I'm trying to use StringioAdapter inside the mailer, and it fails because `length` used in one of the `mail` gem:
https://github.com/mikel/mail/blob/master/lib/mail/message.rb#L1997

Also you can see that normally `size` has `length` alias, for example in a `StringIO` class:
http://ruby-doc.org/stdlib-1.9.3/libdoc/stringio/rdoc/StringIO.html#method-i-length

Let me know, if this change requires test case, I will add it.

Turns out that aws-sdk v2 isn't backwards compatible in the slightest,
so we should cap that at v1. And cucumber 1.3.17 was giving issues with
ruby 2.2.0. So let's update those.

Update copyright to 2015.

As referenced in #1739

Just because the `Rails` constant is defined, it doesn't mean we're
actually in a Rails app. Since there are people who use Paperclip
outside of Rails, and there's no reason we shouldn't be able to run in
those situations. This commit checks for `Rails.env` instead of just
checking for `Rails` and assuming `Rails.env` works.

typo in NEWS

typo! :nails:

Change to `appraisal install`

This reverts commit 06802254.

Full test not a here ?

executing to `rake appraisal:install` log

```
`rake appraisal:install` task is deprecated and will be removed soon. Please use `appraisal install`.
```

Cocaine changes how it returns the supplied path in 0.5.5. While this
has no effect on the workings of Paperclip in a normal capacity, it does
break the tests. This change fixes that and updates the cocaine
dependency to 0.5.5.

Added manual installation instructions for `file.exe` on Windows

Turns out that between fog 1.22.0 and fog 1.25.0, there was a change to
how fog builds S3 expiring URLs. This changes to test to be the common
point between the two versions. All we need to do here is make sure that
the expiring URL is being constructed.

In the process, this also updates all the appraisal-generated
Gemfiles.

Also, in the process, this meant I had to take away the builder version
restriction. This was put in so that `bundle`ing wouldn't take forever,
but I'm unsire whether this needed to happen with this version or if
builder just needed to be separate from the Gemfile. I'm commimtting
this and asking the people who reported the problem. If you don't see a
revet commit, everything was fine.

This reverts commit ae3ec237.

This reverts commit 8d70c198.

This reverts commit 8e0eb4ce.

During the fixing of the previous commit, the tests broken. Turns out
that between fog 1.22.0 and fog 1.25.0, there was a change to how fog
builds S3 expiring URLs. This changes to test to be the common point
between the two versions. All we need to do here is make sure that the
expiring URL is being constructed.

In the process, this also updates all the appraisal-generated Gemfiles.

Also, in the process, this meant I had to take away the builder version
restriction. This was put in so that `bundle`ing wouldn't take forever,
but I'm unsire whether this needed to happen with this version or if
builder just needed to be separate from the Gemfile. I'm commimtting
this and asking the people who reported the problem. If you don't see a
revet commit, everything was fine.

```
 paperclip $ rspec spec/paperclip/integration_spec.rb --profile 1
Testing against version 4.1.7
.........................[deprecated] I18n.enforce_available_locales will default to true in the future. If you really want to skip validation of your locale you can set I18n.enforce_available_locales = false to avoid this message.
.........

Finished in 15.19 seconds (files took 0.60155 seconds to load)
34 examples, 0 failures

Top 1 slowest examples (9.54 seconds, 62.8% of total time):
  Paperclip Many models at once does not exceed the open file limit
    9.54 seconds ./spec/paperclip/integration_spec.rb:18
```

to

```
 paperclip $ rspec spec/paperclip/integration_spec.rb --profile 1
Testing against version 4.1.7
.........................[deprecated] I18n.enforce_available_locales will default to true in the future. If you really want to skip validation of your locale you can set I18n.enforce_available_locales = false to avoid this message.
.........

Finished in 10.95 seconds (files took 0.59585 seconds to load)
34 examples, 0 failures

Top 1 slowest examples (5.33 seconds, 48.7% of total time):
  Paperclip Many models at once does not exceed the open file limit
    5.33 seconds ./spec/paperclip/integration_spec.rb:18
```

at trim indent

@see https://github.com/thoughtbot/paperclip/commit/804b4edc1d8d7ca9865170e34f26da7d66f6d0d5#commitcomment-8497017

Including + now.

Many people have complained that the Media Type Spoof Detection does not
work properly for their files. While whitelisting is available for some
files, it's not a general solution. This option leaves the "secure by
default" of the media checker in place, but allows people to turn it off
completely if they so choose.

Column-specific options can be specified by using its name,
for example:

```
t.attachment :avatar, created_at: { index: true }
```

Fix: Typo in README

Update README.md

Added a security shield from Hakiri. It shows how secure gem dependencies are.

Update zh-TW.yml

Update zh-CN.yml

Add all sorts of Chinese translations

Use proper name for zh-TW locale.