[bugfix] File wasn't closed explicitly, add implicit close by with statement

PyLoT.py

@@ -3475,7 +3475,7 @@ class Project(object):
         File structure (each row): event, date, time, magnitude, latitude, longitude, depth
         separated by :param:separator each.
         '''
-        infile = open(filename, 'r')
+        with open(filename, 'r') as infile:
             for line in infile.readlines():
                 eventID, date, time, mag, lat, lon, depth = line.split(separator)[:7]
                 # skip first line