preview data file

ui and slot to preview first 10 lines of data file
Merge branch 'master' of local repository into paths
Merge branch 'paths' of https://github.com/iled/gsimcli.git into paths
fixed paths manipulation

. using given args outputdir and outputfile instead of dss par
. forcing relative nt paths, two levels down (instead of three), both
for input and output
fix for batch_decade using given results path

. batch_decade with arg for network_id (optional)
. use given (decadal) data directory, if not try to guess from variogf
. clarified some docs