Mobile improvements

[zr0w1]

Note: these changes have only been tested on Safari and Chrome on iOS

To prevent the keyboard from popping up by default I use the inputmode attribute which signals to the browser which virtual keyboard to display (eg: inputmode=numeric may show the 'keypad' instead of a typical keyboard). Setting this to none tells the browser not to display any keyboard. In this case, mobile users will need to tap input fields to show a keyboard. Since desktop users use hardware keyboards they are unaffected. Closes #424

[11k]

I did some research and suspect this won't work properly on Android. According to this article, Chrome for Android won't get a keyboard at all. The article is a little dated, admittedly.

Generally speaking, the docs are clear this is meant to be used only when the app renders its own keyboard. Even though it might have the desired effect, I'm concerned this approach will have issues.