Added `yii\console\Controller::EXIT_CODE_NORMAL` and `yii\console\Controller::EXIT_CODE_ERROR` constants, `yii\console\MigrateController` now returns `yii\console\Controller::EXIT_CODE_ERROR` in case of failed migration

issue #2852

adjust existing Console Controllers and docs

fixes #33

This reverts commit 9d7597d6, reversing
changes made to 6b6390f7.

Result of a discussion with @qiangxue
- there is not global Yii::$app->response anymore, every action has
  dedicated response class
- implementation allows using HMVC pattern now, nested actions do not
  interfer

issue #33
- implemted getScreenSize for linux systems
- tiny adjustments and better naming for console color methods
- color switch in base Controller changed to magic property
- colorized Help command

changed name of ansi switch to --colors
https://github.com/yiisoft/yii2/commit/69cad905dd049be9d9b35d8103cd60591e13c6ae#commitcomment-3168489
issue #33

also naming of formatString -> ansiFormat

added method wrappers in console/Controller

issue #33

Appended newlines to every PHP document that did not have a newline as the last character in the file.

I18N WIP.