title: Override properties when including a psake script in an other psake script
body: <p>I am new to psake and I have this issue: I have 2 psake scripts:</p>
  
  <p>(1): base_tasks.ps1:</p>
  
  <pre><code>properties{ 
  
  $a = "hello"
  
  $b = "hi"
  
  }
  
  task One{
    Write-Host $a
  }
  </code></pre>
  
  <p>(2): install.ps1</p>
  
  <pre><code>Include .\base_tasks.ps1
  
  properties{ 
  
  $a = "Goodbye"
  
  $b = "Adjeu"
  
  }
  
  task default -depends One
  </code></pre>
  
  <p>Now, is it possible to override the properties and variables from file 1? I want to use file 1 as "base tasks" and use those tasks in the install.ps1 and override the properties. Or do I have to do that an other way? I will invoke install.ps1 and use my $a and $b from install.ps1.</p>
  
  <ul>
  <li>DanceAlot</li>
  </ul>