Have PDF Export check to ensure page is rendered before allowing export

Currently, PDF exports can grab a large amount of CPU and memory if a page contains a number of executing macros and templates. If the page has not completely rendered before the export to PDF function is used, then a system can be slowed while the CPU and RAMare taxed during a PDF export which will attempt to render the same macros already underway before that page is fully rendered. This leads to the same macros being executed twice on a page, and doubles the amount of resources needed to render same.

As a feature request, it would be nice to have the PDF export:

1. Not available until the page has rendered fully
2. Only render a static version of the page, and not attempt to re-render any macros that are executed such as live templates, reporting or future macros, that add normal processing time and cycles

This would prove beneficial in lowering the CPU and RAM usage, and help improve overall performance and stability in the system.