RdWr - that line not needed anymore
RdWr - comments added to test
RdWr - bug fixed - if error goes right after readahead data, we add undef with previous data
RdWr - rewrite read in Readahead.pm without recursion, not breaking any tests
RdWr - readahead should not return undef
RdWr - tests for readahead setting err/eof
RdWr commend added