Avoid buffer overrun in config_parse_str()
Avoid buffer overrun in config_parse_str()

The previous implementation only read a prefix from the configuration
file if the configuration value was too long and forgot to terminate the
string with a NUL character.

Return 0 if the string is too long instead.

Signed-off-by: Lukas Fleischer <c9ca73f8336dcfb037ec2c2abf52d80a6847a5cd@calcurse.org>

lfos/calcurse,lfos/calcurse,lfos/calcurse