partial implementation of daily update check
Merge branch 'apks' into apks-update

Conflicts:
	mobile/android/app/mobile.js
	mobile/android/modules/WebappManager.jsm
start reimplementing updates to be APK-centric
Merge branch 'apks' into apk-updates
readd files removed by merge
get outdated apps
getApkVersionNumbers working with initial 'check unknown sources' checkbox ui
Revert "getApkVersionNumbers working with initial 'check unknown sources' checkbox ui"

This reverts commit 5c1b431f9b58406ef3e626f741bdf2962b19a804.
Merge branch 'apks' into apk-updates

Conflicts:
	mobile/android/app/mobile.js
	mobile/android/base/tests/testWebapp.java
	mobile/android/components/MobileComponents.manifest
	mobile/android/modules/WebappManager.jsm
implement APK version retrieval
add URL of fake update check service
remove test file (will reland in branch implementing test)
Merge branch 'apks' into apk-updates
fix determination of the biggest icon URL for an app
Merge branch 'apk-about-apps' into apk-updates
add button to about:apps to manually check for updates
make the app update check work; simplify APK version retrieval; rename xhr to request
logStringMessage -> dump to correct log level from error to info; remove extraneous and distracting filename and emphasizers from message
download/install APKs for outdated apps
remove unused code block