tuned -- more standard operations;

File.bash_string operations in ML as in Scala -- exclusively for GNU bash, not perl and not user output; clarified treatment of whitespace in some bash scripts;

clarified treatment of DEL; tuned signature;

clarified RAW_ML_SYSTEM;

tuned;

Bash.process always uses a closed script instead of an open argument list, for extra robustness on Windows, where quoting is not well-defined; more robust File.bash_escape; more robust treatment of ML_OPTIONS; clarified prover args (again);