[UX] Login > optimise input for username

[michaelstingl]

ownCloud usernames can contain "." and "@" quite often. Would it make sense to use the "Email"-type iOS keyboard when entering the username?

Basic Auth (now)	SFAuthenticationSession (now)

To show a different in the web UI, a change in the ownCloud server would be necessary… (<input type="email"></input>)

More information:
https://developer.apple.com/library/archive/documentation/StringsTextFonts/Conceptual/TextAndWebiPhoneOS/KeyboardManagement/KeyboardManagement.html

Expected behaviour

Entering the username would be easier with the "Email"-type iOS keyboard

Actual behaviour

Users have to switch to the 2nd page of the keyboard to enter the "." and "@"

Client

iOS version:
iOS 12.1.2 (16C101)

ownCloud app version:
ownCloud beta version 1.0 build 85 (5df9764)

Device model:
Model: iPhone XS Max