Run tflint on *.hcl files

[Georgi D. Sotirov]

Introduction

Tflint is capable of verifying *.hcl files (e.g. Terragrunt configurations), but currently I have to rename these to *.tf, which is inconvenient. It would be nice if I'm able to run tflint also on *.hcl files with some argument.

Proposal

Allow checking of *.hcl files with an argument (e.g. --hcl or --check-hcl).