Add support for recursive init and print versions

[wata727]

Follow up of #1622

This PR changes --init and --version to support the --recursive option. As a result --chdir is also supported:

$ tflint --recursive --init
Installing plugins on each working directory...

====================================================
working directory: .

Plugin `aws` is already installed
====================================================
working directory: sub1

No plugins to install
====================================================
working directory: sub2

No plugins to install
====================================================
working directory: sub3

No plugins to install
====================================================
working directory: sub3/sub

No plugins to install

$ tflint --recursive --version
TFLint version 0.43.0

====================================================
working directory: .

+ ruleset.aws (0.21.1)
+ ruleset.terraform (0.2.1-bundled)
====================================================
working directory: sub1

+ ruleset.terraform (0.2.1-bundled)
====================================================
working directory: sub2

+ ruleset.terraform (0.2.1-bundled)
====================================================
working directory: sub3

+ ruleset.terraform (0.2.1-bundled)
====================================================
working directory: sub3/sub

+ ruleset.terraform (0.2.1-bundled)

This is a missing piece for the recursive inspection introduced in #1622. The recursive inspection will load each directory's config, so you'll need to tflint --init in each directory. The tflint --recursive --init solves this.