Modify formatting and templates

I refer to the docs a bit, and I've found it somewhat hard to find things. Sometimes I must do a ctrl-f to find the route I need details about. The leftnav TOC with H3s really helps me, hope it helps you too.

The docs css is modified as well. 

I'd build upon this with a collapsable menu but I'll leave that to your CSS expert.

Just in case, I inlined the DCO.