GitLab

* update docs for ray gradients

* update pdf

* zeros -> emtpy in cuda

* disable cuda hint if is been built

* update examples with better perf

* bump version to 0.2.0

* update readme

* update index and readm

* clean up doc

* new logo

* size

Co-authored-by: Xiaoming Zhao <xmzh@fb.com>

* update doc and bump version

* update docs with final scores

* ngp doc

* fix doc title

* benchmark ngp is done.

* finer training schedule for mlp-based nerfs

* slightly doc update

* update index

* update doc title

* update to pip install

* cleanup docs