updated requirements.txt
ignore old venv dir
Fix the bracket problem with links
Updates to better handle pando source items
Added threading to the source filling in
Added ability to get markdown without initial_html included
Cleaned up printed output
Catch 404 errors when fetching pando sources
Added support for two textareas in the editor when loading from pocket.

This sort of screws up saving (since it won't save the bottom one) so
you have to copy everything you want to the top one if you're going to
leave the page.  Oh well.