Cleanup naming conventions for using voxel addons

Moving closer towards unifying on this convention:

createFoo = require('foo')
foo = createFoo(game, opts)
Update voxel-oculus to use factory export convention: https://github.com/deathcap/voxel-oculus/commit/aa7d5efd8821105497983c32acca21cc39a08a35
Disambiguate controls target
Consistent highlight and mining reach distance (8 blocks)
Disable adjacent highlighting on Ctrl since place blocks with right-click instead
Update to use object-oriented voxel-walk

More in line with the other voxel addons conventions
Requires https://github.com/deathcap/voxel-walk/commit/050d01ff20aeff669ac4ae411be7e41e35d4ba46
Move walking event listener into voxel-walk

Requires https://github.com/deathcap/voxel-walk/commit/f1971ebd058ec747cc507ca9b86acc8279ff106b