sync: easier configuration (fixes #3742)

[ewhang5]

Additions:

• Implemented UI of MaterialButtonToggleGroup and MaterialButtons
• Improved some other UI aspects of

TODO:

• Remove SYNC button
• Move functionality so that when any of the MaterialButtons is pressed, the sync is automatically triggered

[Okuro3499]

Remove SYNC button
Move functionality so that when any of the MaterialButtons is pressed, the sync is automatically triggered

@ewhang5 about the implementation of the above, what if a wrong server is selected by mistake
will we have a button to cancel sync?
what will be the implications of this to the couch db?

[ewhang5]

Remove SYNC button Move functionality so that when any of the MaterialButtons is pressed, the sync is automatically triggered

@ewhang5 about the implementation of the above, what if a wrong server is selected by mistake will we have a button to cancel sync? what will be the implications of this to the couch db?

@Okuro3499 this was also a slight concern of mine, but dogi wanted the sync to happen automatically. I think if the user tries to sync to a new server, they should still receive the same prompt asking for a confirmation, so hopefully that can work to allow for cancelling a sync. What do you think about this?

[dogi]

#3982