New feature: queXMLPDF export with response data

Dev: Updated queXMLPDF generation to support inserting response data
Dev: Add icon when viewing responses to allow for a queXMLPDF exports containing response data
Dev: Add button when printable answers enabled for respondent to download queXMLPDF containing response data
Dev: Refactored for develop branch
Dev: Fixed template display for queXMLPDF export
Dev: Added {QUEXMLPDF} button for template
Dev: Fix spacing