Added support for modulus operator in expressions

CSVREAD / CSVWRITE: instead of setting the options one by one, all options can be combined into a space separated key-value pairs.

CAST: when converting a string to binary, it is hex encoded (every byte two characters); a hex string can be converted to a number by first converting it to binary.

It is now allowed to truncate a table if referential integrity has been disabled for this table or database.

Support for null-safe equals. This includes the ANSI SQL standard syntax A IS [NOT] DISTINCT FROM B as well as the shorter A IS [NOT] B.

CREATE VIEW now supports the OR REPLACE clause