Reset class at each call

[enorazza]

I was having a weird behaviour using the class: the second time I generated the shapefile was the result of the merge of the previous geojson file and the latter.

Solved added a reset function and a call "self.reset()" as first line in the __init function

def reset(self):

    self.geometryType = ''

    self.columnsList = []

    self.__attributesPerF = []

    self.attributes = []

    self.geometries = []

    self.shpFileObj = None