Added Other Devices menu
Other Devices tabs are retrieved using the chrome.sessions API, which is only available in the dev channel for now

TODO: test using dev build of chrome
TODO: localization
Tested & debugged on dev build 35.0.1916.6 dev-m
Added scrollbars if the list gets too big
TODO: add collapse per device

Added timeago
Fixed timeago localization script loading
Fixed dutch locale json
don't disable other devices if the list is empty (list may take a while to load, and when clicking the button whe it's not loaded yet we don't want it to dissapear)
added todo
moved check for chrome.sessions to be executed only once
Merge VEH001 - Add "Other devices"