Restructure data load/save

[poloskeipeter]

I would like to move where the file extension is being resolved in the current load signal / save signal functions completely to the core as a method.
What should stay in the main are 4 functions (2 for raw signal load / save and 2 for processed load / save)
The code I envisaging should look something like:

def loadSignal(self):
    self.loadSuccessful = False
    self.data.__init__()
    path = QtWidgets.QFileDialog.getOpenFileName()[0]
    try:
        self.data.loadRawSignal(path)
        self.loadSuccessful = True
    except:
        print('unrecognised file format or data')

[martonvavrik]

The dataobject in core has functions for loading raw and processed sav files in itself (.load_proc_sav and .load_raw_sav). It also has a (now working) .save and a .load function, which saves/loads all contained flap dataobjects, with no regard to their origin.

[gergopokol]

Is this still relevant?