Allow form import from file (in browser).
Allow form export to file (in browser)
Merge branch 'wip-prefstore' into wip-browser-import

Conflicts:
	chrome/content/js/geierlein.js
Add foreign data import, refs #19
Merge branch 'wip-browser-import', closes #19

Conflicts:
	chrome/content/index.html
	chrome/content/js/geierlein.js