webif: initial web interface support via flask/flask-restless

A basic web interface is present that can show some information out
of the database.  Unfortunately, flask-restless doesn't seem to want
to include DateTime fields, so I may end up ditching that and just
generating the history server side and using polling with something
simpler for the download queue.
webif: history page is now reasonably functional
Merge branch 'master' into webif

Conflicts:
	putiosync/core.py
download_manager: initial working implementation of download manager

This has the same level of fuctionality as was previously present but
using the new "DownloadManager".  This has the hooks that should let
us build web functionality showing active downloads in the future.
webif: it isn't beautiful, but we now have progress bars on active download
webif: cleanup client-side code using handlebars and make things look nicer
webif: instantaneous download rate and graphs!
webif: fix bug with display KB
webif: add record of recenlty completed
webif: fix bug where empty directories were not removed

Also add link to "put.io" in the navbar.
Merge remote-tracking branch 'origin/master' into webif
unicode: deal with unicode by dropping non-ascii bytes

This seems to work for the cases I have encountered as filesystems
tend to be hit-and-miss on unicode.
webif: open a webbrowser window on application launch and change port
unicode: fix unicode encode bug