feat: MarkX.Header ( Fixes #33 )

Returning object with header, and text with yamlheader.  Allowing object or text set for either.

Author: StartAutomating

Types/MarkX/get_Header.ps1

@@ -0,0 +1,9 @@
+if (-not $this.'#YamlHeader') { return }
+
+$convertFromYaml = $ExecutionContext.SessionState.InvokeCommand.GetCommand('ConvertFrom-Yaml', 'Alias,Cmdlet,Function')
+if (-not $convertFromYaml) {
+    Write-Warning "Cannot get header without ConvertFrom-Yaml"
+    return
+}
+
+return ($this.'#YamlHeader' | & $convertFromYaml)

Types/MarkX/set_Header.ps1

@@ -0,0 +1,3 @@
+param($header)
+
+$this.YamlHeader = $header