First commit of SecureCRT import functionality.

[magriggs]

Description

Import SecureCRT file format into mRemoteNG.

Motivation and Context

#2487

How Has This Been Tested?

SecureCRT file created as Resource in unit tests project. Unit tests written to cover import functionality
NB: there are still 67 failing unit tests in the project, unrelated to this PR.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• [ X ] New feature (non-breaking change which adds functionality)
• Changed feature (non-breaking change which changes functionality)
• Changed feature (breaking change which changes functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Updated translation

Checklist:

• [ X ] I have read the CONTRIBUTING document.
• [ X ] My code follows the code style of this project.
• [ - ] All Tests within VisualStudio are passing
• [ X] This pull request does not target the master branch.
• I have updated the changelog file accordingly, if necessary.
• I have updated the documentation accordingly, if necessary.