Removed extra slashes so the local file paths work in Windows.
Fix for case when WKHTMLTOPDF_CMD consists of many parts.
Merge pull request #23 from shadowrock/fix-multipart-cmd

Fix for case when WKHTMLTOPDF_CMD consists of many parts.
Remove duplicates when replacing file paths
Merge pull request #25 from zgohr/duplicates

Remove duplicates when replacing file paths
Merge pull request #21 from shadowrock/fix-extra-slashes

Removed extra slashes so the local file paths work in Windows.