Added mask, better page labels, and more!

- Added some layout styles and introduced a new preview pane on the
  right side of the page.
- Now there's a <canvas> mask that darkens the unselected portion of the
  map. It's a bit laggy on pan, but it works!
- Labels are now much nicer, and work well on the Bing lightened tiles.
  Some work will be needed to get these looking good on OSM.
Working on form submission...
added tabloid sizes
added paper size and orientation, buttons, etc.
Merge
Merge branch 'atlas-ui-sketch' of github.com:stamen/paperwalking into atlas-ui-sketch
Adding ability to preview field papers
Fixing typo
Fixing field papers preview
Merge branch 'atlas-ui-sketch' of github.com:stamen/paperwalking

Conflicts:
	site/templates/en/index-features-paragraph.htmlf.tpl
Making more fixes to the field papers preview
Merge branch 'atlas-ui-sketch' of github.com:stamen/paperwalking
Cleaning up HTML on incidents page
Making the features links relative
Worked around a bug in GDAL by forking off a child process and watching its exit status
Added handler for keyboard interrupts
oops
Merge branch 'master' of github.com:migurski/paperwalking

Conflicts:
	decoder/decode2.py
	site/lib/data.php
	site/templates/about.html.tpl
	site/templates/compose.html.tpl
	site/templates/footer.htmlf.tpl
	site/templates/index.html.tpl
	site/templates/language.html.tpl
	site/templates/navigation.htmlf.tpl
	site/templates/print.html.tpl
	site/templates/prints.html.tpl
	site/templates/scan-large.html.tpl
	site/templates/scan.html.tpl
	site/templates/scans.html.tpl
	site/templates/unavailable.html.tpl
	site/templates/upload.html.tpl
	site/templates/uploaded.html.tpl
Adding aspect ratio selection; adding ability to deal with arbitrary number of incidents
Adding new stylesheet for csv demo