I added logic of refreshing items.
guide upload
redesigned png
I did small things. I have to change login logic.
I changed sign in setting save timing. I have to change UI.
Merge branch 'master' of https://github.com/hongkunyoo/pin_the_cloud
Fixing each storage login logics
Merge branch 'master' into hongkun

Conflicts:
	PintheCloud/Managers/GoogleDriveManager.cs
	PintheCloud/Managers/OneDriveManager.cs
	PintheCloud/Pages/ExplorerPage.xaml.cs
finished fixing login cancel bug