[Add] gitignore and .\external\ssh2 from fex

Signed-off-by: Oleg Komarov <o.komarov11@imperial.ac.uk>
[Change] sas2csv.m, creates csv

Signed-off-by: Oleg Komarov <o.komarov11@imperial.ac.uk>
[Change] sas2csv.sas: avoid proc export

Signed-off-by: Oleg Komarov <o.komarov11@imperial.ac.uk>
[Add] write compressed output

Signed-off-by: Oleg Komarov <o.komarov11@imperial.ac.uk>