Merge pull request #745 from garvankeeley/refine-disk-db

Data storage timer bugs: (1) upload timer kept being reset (2) new idle timer to flush
Add Romanian translation
sync zh-CN translations with en-US strings
Merge pull request #753 from danniel/master

Add Romanian translation (@danniel)
Merge pull request #754 from l-hedgehog/zh-cn

Update zh-CN translations (@l-hedgehog)
Use the last map center (not necessarily the last user location), instead of (0,0)
Update zh-TW strings
Typo fixed

Sorry, my bad.
Merge pull request #756 from yarons/patch-1

Typo fixed in Hebrew strings (@yarons)
Merge pull request #755 from petercpg/0805_zhtw

Update zh-TW strings (@petercpg)
Merge pull request #739 from keverets/save-last-map-location

Use the last map center (not necessarily the last user location), instead of (0,0)
Use MapQuest OSM tiles instead of Mapnik

Members of OSM recommended making use of the free MapQuest tiles
instead of leaning on the mapnik infrastructure.  More information
available at:

http://developer.mapquest.com/web/products/open/map
Move CoverageOverlay to its own class
When zooming greater than the tile provider's ability, scale the upper zoom layer
Better ensure that each tile gets drawn only once

Use a set to keep track of what has been drawn.  This isn't efficient, and
could use some refinement.
Merge pull request #770 from keverets/mapquestosm

Use MapQuest OSM tiles instead of Mapnik
Merge pull request #769 from keverets/coverage-overlay-zoom

Coverage overlay zoom
Make default zoom 16 rather than 13
Include new logos

Taken from https://github.com/mozilla/ichnaea/tree/master/ichnaea/content/static/images
Merge pull request #776 from keverets/new-icon

Include new logos (@keverets)