[doc] update to readme.txt
[enh] outfactored [en|de]crypt in chaining, for buffered operations
[enh] added buffered mode for [en|de]crypt
[mod] help text
[fix] wrong params in test?
[doc] better test.sh output
[enh] added clearing of sensitive memory and locking of process against swap
[enh] reordered keycheck_handler next to keysign_handler