FIX: pointer location in file
FIX: set buffer_size_sec=1 to the test_read_segment functionality
ADD: test when preload=False and read a segment of data

FIX: test on raw_edf instead of Raw
FIX: int to float by division
STY: add space between standard and external modules
Merge pull request #1000 from t3on/tb-edf-FIX

FIX edf reader: pointer location in file