Improve appearance of documentation site

[MRdep]

Site appearance is a little ugly.

• need to remove contents and and navigation from sides.
• add navigation to top bar.
• need to increase appearance size of OSIPI logo
• remove bullet points,

[MRdep]

I've tried to remove toc to allow more room for tables, following squidfunk/mkdocs-material#478 but it doesn't seem to work.