add runtimeviewer caching option

[unitycoder]

so after you have parsed the file once, it could save it into .bin file for faster reading next time.
(if [x] save cache is enabled)

*or basically just allow the converter to be run at runtime, to make .bin files.

[IsDon]

Could we have any pointcloud saved with randomise points option into a new binary file [Editor]? Randomise on load is a slowdown that seems unnecessary.

[unitycoder]

next version has caching (resave) option for binaryviewer also (to save randomized cloud),
until have converter version that supports randomizing.

[unitycoder]

binary v2 and v3 formats support randomizing from converter, and there was caching option added for viewers.