[Bug] Respect font scaling

[Vorror]

This is a (multiple allowed):

• [x] bug
• [ ] enhancement
• [ ] feature-discussion (RFC)

Actual Behavior

Framework7 does not currently respect the iOS font scaling.

iOS with default font scaling

iOS with large font scaling(not working)

Expected Behavior

Respect os font scaling

Background

We have a lot of users who don't use the default iOS font scaling. Here's some tech info in regards to supporting scalable fonts: http://www.interactiveaccessibility.com/blog/text-resizing-web-pages-ios-using-dynamic-type

I can confirm using their test page (http://ia11y.github.io/Coding-Patterns/iOS/text-resizing/resizable-vs-non-resizable-font-ios.html) that the font does scale on iOS devices.

Basically this would require a switch to em font sizes. I see there's a v3 of framework7 in the works, maybe this could be a feature for that version?

[Vorror]

For the most part F7 could simply convert px -> em css:font-size's using a less mixin. Although any parent elements that have hard coded widths/heights would need to be fixed by doing something reasonable(truncating text, line-breaking, etc)

[nolimits4web]

Rewriting all font sizes to em doesn't seem a good option for me. Will take a look what can be done here