Ensure changelog render is consistent with all line separator

[danygold]

Pull Request Details

This pull request should fix #182 , and ensures that changelog render is consistent with all line separator.
In this moment, LF line separator works properly, but instead CRLF and LF have some bugs/different behaviour.

Description

While the purpose of PR #177 was only to fix a regresion, the goal of this PR is to ensures that changelog render is unbiased to line separator.

In particular:

• Added a new optional parameter lineSeparator to markdownToHTML helper method
• markdownToHTML and markdownToPlainText now convert line separator to LF before AST parsing.
• Fixed reformat method (Some regex work only with \n or \r, but not with \r\n, due to missing group)
• Added a new assertText method, useful for test that plain text output strings are equals (Without improperly using assertMarkdown)
• Ensure that processOutput normalize line separator also for OutputType.MARKDOWN (In same cases, joinToString and reformat is not enough and generate a content that contains different line separators)

Related Issue

• Wrong render in changelog file that use CRLF #182

Motivation and Context

While the purpose of PR #177 was only to fix a regresion, the goal of this PR is to ensures that changelog render is unbiased to line separator. See also #182 to see some cases that this PR fix.

The solution applied is the same of #177, so:

• Before parsing changelog using markdown library, convert line separator to LF.
• After parsing, restore the correct line separator.
  but this time the behaviour is applied to all code that use the markdown library.

See also markdown bug

How Has This Been Tested

I have added some unit test, that cover my modification. All new and existing tests passed.

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the README.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[hsz]

Great job, Daniele — thanks!