Add Readme and Docs

[lgeiger]

• Link to paper
• Link to implementation
• Table to compare models
  • Top-1 accuracy
  • Top-5 accuracy
  • Number of parameters
  • Number of MAC operations
• Publish on github pages: https://plumerai.github.io/larq/

[jamescook106]

I assume this is to be done on a per model basis, so it's a good idea if the author of every models add the documentation themselves. We need the profiling tools from @arashb (as per larq/larq#91) to do the last 2 points