Bumped to 0.7.4.1

Overhauled installer -- fixed a number of small bugs
Better output during installation
Complete uninstaller - removes services, etc

SABnzbd/tools/WaitForSuccess.ps1

@@ -0,0 +1,24 @@
+function WaitForSuccess([ScriptBlock] $script, [int]$seconds = 10,
+  [string]$description = 'operation to complete')
+{
+  $skip = $false
+  Write-Host "Waiting up to $($seconds)s for $description..."
+  $result = 0..($seconds * 2) |
+    % {
+      if ($skip) { return $true }
+      $status = &$script
+      if ($status -eq $true)
+      {
+        $skip = $true
+        return $true
+      }
+      elseif ($service)
+      {
+        Start-Sleep -Milliseconds 500
+      }
+      return $false
+    } |
+    Select -Last 1
+
+  return $result
+}