Moved build instructions and docker instructions to separate docs.
Removed command samples which are no longer needed as we have better
tutorials now.
Change-Id: I340c5653a6553158325970dd86d76fa11e69bcbd
Build sphinx docs in docs/ directory:
$ make html
The outputs are created in out/sphinx directory.
Change-Id: I040915a30aa52d41b18e04741e45622fa61244f6