[Fix] getData: retrieves Datetime if Time is not there

Signed-off-by: Oleg Komarov <o.komarov11@imperial.ac.uk>
[Fix] fixedsampling: actual dates was using old version of nanfillts

Signed-off-by: Oleg Komarov <o.komarov11@imperial.ac.uk>
Merge branch 'master' of git@github.com:okomarov/HFbetas