* tests env in a vacuum as well as testing Amber.env

* tune

* encorporated suggestions

* defaults amber version to the same version as the cli

* changed spec to test this scenario

Amber currently ships with 3 different environments: development, test
and production.

As a developer I would like to sometimes run code conditionally
depending on the environment that the application is.

```crystal
if Amber.env.development?
  # ... code here ...
end

```

This PR addresses the issue by creating a Amber::Env module that
contains 3 module methods:

```crystal
Amber.env.development?
Amber.env.test?
Amber.env.production?
Amber.env.integration?
Amber.env.staging?
Amber.env.sandbox?

Amber.env.in? %w(development test)
Amber.env.in? %i(development test)

Amber.env.is? "test"
Amber.env.is? :test
```

With the changes in this PR a developer should be able to call the
appropriate method to check for the desired environment.

Adds Additional Module methods

`in?` and `is?` methods to check for inclusion of the environments

Uses rails style for Amber environment checks

* Extract CSS from JS bundle

It moves all the required *.css modules in entry chunks into a separate CSS file.

- Faster runtime (less code and DOM operations)
- Styles are no longer inlined into the JS bundle.
-  If your total stylesheet volume is big, it will be faster because the CSS bundle is loaded in parallel to the JS bundle.

* Update generated bundles

* Update generated bundle

* Remove webpack plugin to minify css

* Use quartz_mailer

* Update quartz mailer name

Add security header for older browsers to prevent content sniffing

* remove static controller

* move to static controller so it doesn't get inherited by other controllers:

* #54 support crecto

* minor bug fixes

* float64

* fix auth migration

* bug fixes

* move requires to application.cr

* fix spec helper requires

the optional parameter rule checked to see if the param was present and only ran the validation block if it was found. If the param is not present it returned nil and this nil was interpreted by the unless clause that checked the rules as a failure. This change allows the rule to pass if the param is not present.

Please see https://github.com/kemalcr/kemal/pull/405/files

* Remove -1 on Content-Range

* Add -1 on fileb

* Add +1 to content_length

 if the range is Range: bytes=0-1023 the content length would be 1023 but it should be 1024.

* fixed issue with render and made it a bit closer to rails render

* fixed spec

* small cleanup for render macro.

* moved render template under render

* Adds deploy and encrypt to readme

amber deplopy [OPTION]          # Provisions server and deploys project. [-s --service | -k --key | -t --tag | -b --branch]
amber encrypt [OPTION]          # Encrypts environment YAML file. [env | -e --editor | --noedit]

* Update README.md

* Remove alias and use Amber::Exceptions::Base

* Use Exception class instead

* Refactoring error pipe

Error pipe was refactored and added inside
router.cr and is part of web and static
pipelines, allowing to add customized error
pages more easily.

- Add Amber::Controller::Error
- Add Amber::Pipe::Error.new to configured pipelines
- Add error_controller.cr
- Format files
- Raise RouteNotFound on StaticController
- Simplify Amber::Pipe::Error
- Call Pipe::Error on Exceptions::Base inside Pipe::Pipeline
- Fix error spec
- Update docker image

* Small refactoring in error controller

Change message_based_on_content_type to response_format and simplify error controller.

- Avoid duplicated code
- Ensure content_type is assigned

* Refactoring colorized output.

* Add --no-color flag.
* Add color to enviroment settings.

* Fix description

* support reference type in generator

This will provide the ability to define a relationship using `ref` or
`reference` as the type when generating a model or scaffold.

* fix indent

* support reference type

* default to localhost

* add select_field for references

* select instead of reject

* fix indent

* add selected to options

* add index for foreign key

* add index to model generator

* change ref to reference

* add belongs_to as an option

* add references for rails devs

* Fix #262

* Fix #245

* Fix #245

* Add X-Powered-By header

* Add spec for X-Powered-By

* Fixes spec

* Update to amberframework.org

* Move context spec to pipeline spec

* Fix pipeline

* Update links from amber-crystal to amberframework.

* Hide logo in small screens.

* fix links on homepage

* update links

Config method was replaced with Configure

* fix image path in webpack

* fix image location. provide better home page.

* remove question mark

* change type of session

I did this to support Symbol, String or Int32 for session settings.
This allows you to use `store: :signed_key` and `expires: 0` in the
environment.yml file.

* use secret_key_base instead of generating a key on restart

* modify tests to match

* fix template for session store

* PR feedback

* remnant of thought

* more cleanup