Use StringBuilder in loop for better performance and ensure resources are recovered regardless of any problems that may occur

add NEW_TASK flags when start settingsActivity

#9 #1707

load saved info when settingsActivity is reloading

retry geoInfo when fail to get geoInfo

#1658

retry geoInfo after 1min.

#1707

add settgins, update button on widget

reorganize views for resizing icons

#1707
add vector icons
show aqi value on aqi widget
remove protected setWidgetStyle
modify update time to download time
display "loading"msg at update is started.

try-catch for ArrayIndexOutOfBoundsException, NullPointerException

rename apppreferences to widget_preferences

set requestCode for Classification

check null of geo info
update format of geoinfo.tostring

move alarmManager to WidgetProvider from Settings

#1486 #1696
move alarmManager to WidgetProvider from Settings
service on foreground

fix wrong save current geo info

#1658
use START_REDELIVER_INTENT for service
use PASSIVE_PROVIDER for getLastKnownLocation
use requestSingleUpdate and Criteria

#1486
use stopSelf(startId)
use alarmManager.setRepeating

#1658 #1486
remove stopSelf()
change geoinfo to savedGeoInfo when new location is the same as saved geo info