Optional compression of the index file

[tophf]

The .lwi index file for a 90 minute movie encoded with 10-bit x264 is 190MB written in hundreds of file system fragments (at least on all windows systems) which makes its initial loading off an HDD quite slow and things get worse in case some applications access this disk in background, just imagine hundreds of mechanical disk seeking operations interleaved with other activity...

On the other hand the HDD access penalty becomes a non-issue with a zip-compressed index file - for the aforementioned 90-minute movie it's only 13MB (7% of original 190MB) at default compression level. I think zlib/gzip/xz/lzma would be even smaller.

So it'd be really helpful if L-SMASH-Works will have a parameter to read/write compressed index files.