BREAKING CHANGE: SecurityOption: append nullchar for network registry paths

[mgreenegit]

Pull Request (PR) description

The intention of this PR is to support the setting for accessing registry paths from the network. The values must use nullchar as a delimiter. The impact of not making the change is any tools that expect this GP behavior and audit the output will identify the characters are missing and mark the value as incorrect.

Task list

• [x] Added an entry to the change log under the Unreleased section of the file CHANGELOG.md. Entry should say what was changed and how that affects users (if applicable), and reference the issue being resolved (if applicable).
• [ ] Resource documentation added/updated in README.md.
• [ ] Resource parameter descriptions added/updated in README.md, schema.mof and comment-based help.
• [ ] Comment-based help added/updated.
• [ ] Localization strings added/updated in all localization files as appropriate.
• [ ] Examples appropriately added/updated.
• [ ] Unit tests added/updated. See DSC Community Testing Guidelines.
• [ ] Integration tests added/updated (where possible). See DSC Community Testing Guidelines.
• [ ] New/changed code adheres to DSC Community Style Guidelines.

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This change is 

[codecov[bot]]

Codecov Report

Merging #155 (08a6355) into master (8969a1b) will decrease coverage by 0%. The diff coverage is 0%.

@@          Coverage Diff          @@
##           master   #155   +/-   ##
=====================================
- Coverage      89%    89%   -1%     
=====================================
  Files           5      5           
  Lines         574    576    +2     
=====================================
  Hits          516    516           
- Misses         58     60    +2     

[gaelcolas]

I'll try to bundle this change within v3 before doing a full release.