Read leading module header from main.tf

[khos2ow]

Prerequisites

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• This pull request fixes a bug.
• This pull request adds a feature.
• This pull request enhances existing functionality.
• This pull request introduces breaking change.

For more information, see the Contributing Guide.

Description

As part of preparing the support for Terraform 0.12 which has been discussed in length (#62 (comment), #62 (comment) and hashicorp/terraform-config-inspect#21 (comment)) we had decided to drop the support of extracting module header comment from main.tf file, but this PR is going to address it with minimal effort, which is internal to terraform-docs codebase and does not depend on Terraform community as a whole and terraform-config-inspect in particular.

Supported comment formats is:

• jsdoc, c or java-like multi-line comment /** **/

BREAKING CHANGE:

• In the JSON format respone, module "Comment" has been renamed to module header.

Issues Resolved

Fixes #146

Checklist

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• I have read the Contributing Guidelines.

Tests

• I have added tests to cover my changes.
• All tests pass when I run make test.

Documentation

• My change requires a change to the documentation.
• I have updated the documentation accordingly.

Code Style

• My code follows the code style of this project.

[git4raj]

Still happening in version v0.10.1. Comments in the main.tf is not coming in the output