Change cursor when navigating + minor cleanup
(cherry picked from commit 8013dbd)
change cursor and put it on dedicated thread when getting metadata for a dataset
(cherry picked from commit 8a5929b)
tiny refactoring
(cherry picked from commit 4f6ea14)
fix status bar issues
(cherry picked from commit 21857ec)
user is asked if files shall be overwritten if already existing
(cherry picked from commit 7e4bb40)
adapted to new NetCDF versions