Remove font-awesome with svg's/custom icon font for the few icons.

[paales]

There currently are only three icons used (for the header?) right? It will save a lot of bandwidth to just remove it. (our designers wont be using font-awesome icons any more, we usually create our own iconfont).

[danslo]

The initial idea was to also use FontAwesome for other visual indicators, such as phone, etc. But we might be better off just using a couple of PNGs.

[danslo]

Added note here, is that we're not only using this for the header, but also for social login icons.