Unclosed quotes

[mbraga-s]

If unclosed quotes are present in the input, a segfault occurs. Although unclosed quotes are not to be considered by minishell, segfaults under any circumstance are unacceptable

minishell: cmd "something

[mbraga-s]

Run a check before the lexer that gows through the input and then runs from the first instance of a quote ( ' or " ) to the next if there's one. In case there isn't a second quote, an error is returned and a new input is requested.