Bs_CsvUtil.class.php: comma separated values - read and write

Features:
supports any separator char sequence, default is semicolon ";".
supports separator characters in the values. eg you use a ; as separator, your line may look like
blah;hello world;"foo";"foo;bar";"this is a ""string""";got it?;foo
as you can see, the values can be in "quotes". if your text uses quotes itself as in the "string"
example, they are escaped in ms-style with 2 quotes. and by using quotes we can even have your
separator inside the text (example "foo;bar").
line breaks. a csv line may spread over multiple lines using crlf in a field value.
see the checkMultiline param and the _checkMultiline() method.