xCluster: Refactored unit test (#82)

- Changes to xFailOverCluster
  - Added new stubs for FailoverClusters module (Tests\Unit\Stubs\FailoverClusters.stubs.psm1) to be able to run unit tests on a computer that does not have or can install Failover Clustering PowerShell module.
  - Added a script file (Tests\Unit\Stubs\Write-ModuleStubFile.ps1) to be able to rebuild the stub file (FailoverClusters.stubs.psm1) whenever needed.
- Changes to xCluster
  - Refactored the unit test for this resource to use stubs and increase coverage (issue #73).
    - Removed the password file (MSFT_xCluster.password.txt) which seemed unnecessary.
  - Test-TargetResource now throws and error if domain name cannot be evaluated (issue #72).
  - Set-TargetResource now correctly throws and error if domain name cannot be evaluated (issue #71).

.gitignore

@@ -2,3 +2,4 @@
 .vs
 .vscode
 node_modules
+.markdownlint.json

CHANGELOG.md

@@ -46,13 +46,26 @@
     press SHIFT+ALT+F, or press F1 and choose 'Format document' in the list. The
     PowerShell code will then be formatted according to the Style Guideline
     (although maybe not complete, but would help a long way).
+  - Added new stubs for FailoverClusters module
+    (Tests\Unit\Stubs\FailoverClusters.stubs.psm1) to be able to run unit tests
+    on a computer that does not have or can install Failover Clustering
+    PowerShell module.
+  - Added a script file (Tests\Unit\Stubs\Write-ModuleStubFile.ps1) to be able
+    to rebuild the stub file (FailoverClusters.stubs.psm1) whenever needed.
 - Changes to xCluster
   - Added examples
     - 1-CreateFirstNodeOfAFailoverCluster.ps1
     - 2-JoinAdditionalNodeToFailoverCluster.ps1
     - 3-CreateFailoverClusterWithTwoNodes.ps1 (this is the example from README.md)
   - Fixed typo in xCluster parameter description.
   - Added links to examples from README.md
+  - Refactored the unit test for this resource to use stubs and increase coverage
+    (issue #73).
+    - Removed the password file (MSFT_xCluster.password.txt) which seemed unnecessary.
+  - Test-TargetResource now throws and error if domain name cannot be evaluated
+    (issue #72).
+  - Set-TargetResource now correctly throws and error if domain name cannot be
+    evaluated (issue #71).
 - Changes to xWaitForCluster
   - Added example
     - 1-WaitForFailoverClusterToBePresent.ps1