Added asElapsedTime function to Formatter

fix User::getReturnUrl() after #2501

Update usage example in comments of db\DataReader

Changed comment again to actually be correct. This is also consistent with the draft of the definitive guide.

Modified example in DataReader usage comment to reference a DB Command function which accepts a SQL string argument.

Changed comment again to actually be correct. This is also consistent with the draft of the definitive guide.

Conflicts:
	framework/base/Formatter.php
	tests/unit/framework/base/FormatterTest.php

typo fix in contoller.md

fixes #2776 renamed default template folder

updated composer docs

Mistake in error message

{max} was used instead of {min} in the error message for the min validator...

Fixes #2775: Added `yii\base\Application::bootstrap` to support running bootstrap classes when starting an application

Finnish translation

small typo fix

fixes #2765