[Add] filter out by share-type code

Signed-off-by: Oleg Komarov <o.komarov11@imperial.ac.uk>
[Minor] compare fixedsampling vs real_price_filt (better)
[Minor] fixedsampling: edit help, minor fix second output check

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