feat(Posh-VsVars): version 0.0.1

- Includes new set of PowerShellHelpers to find
   standard module directory

core/PowerShellHelpers.ps1

@@ -0,0 +1,37 @@
+function Get-ModuleDirectory
+{
+  [CmdletBinding()]
+  param()
+
+  # find the first default module path we can safely write to
+  $defaultModulePath = $Env:PSModulePath -split ';' |
+    ? {
+      Write-Verbose "Checking path $_ for write-ability"
+      try {
+        if (!(Test-Path $_)) { New-Item -Path $_ -Type Directory }
+
+        $testFile = Join-Path $_ 'write-test.tmp'
+        '' | Out-File -FilePath $testFile
+        Remove-Item -Path $testFile
+        return $true
+      }
+      catch { return $false }
+    } |
+    Select -First 1
+
+  if ($defaultModulePath) { return $defaultModulePath }
+
+  # no defaults were acceptable, so try Choc paths
+  $tools = Join-Path $Env:SystemDrive 'tools'
+  if ($Env:Chocolatey_Bin_Root)
+  {
+    $tools = Join-Path $Env:SystemDrive $Env:Chocolatey_Bin_Root
+  }
+
+  if (!(Test-Path $tools))
+  {
+    New-Item -Path $tools -Type Directory | Out-Null
+  }
+
+  return $tools
+}