Ensure correct level is passed to lzma.
Avoid branch when wrapping rabin window position and check for rabin window size to be power of 2.
Update rabin parameters check for adaptive modes.
Add detection of 7-bit text/8-bit binary data for later use.
Restructure compression functions to take chunk flag as argument.
Add missing error flag printing in LZMA.
Only create enough threads as needed by chunk size and file size.
Minor cleanups and variable name changes.
