fixes #1161

[ci skip]

Method 'yii\mail\MailerInterface::compose()' reworked allowing rendering message body.

- 'body()' renamed to 'renderBody()'
- new 'body()' method introduced

Method 'yii\mail\BaseMailer::compose()' updated, allowing composition of the complex methods like 'renderText' and 'body'.

- setter methods renamed to have pure name
- method 'createMessage' renamed to 'compose'

issue #1140

now also gets stderr output.

fixes #1140

- refactored replaceNamedArguments.
- ensure gridview message works on all systems.

fixes #1072

MessageInterface::render() replaced by MessageInterface::renderHtml() and MessageInterface::renderText()